Antibodies to receptor for oncostatin M

ABSTRACT

A novel polypeptide functions as the β chain of an oncostatin M receptor and is thus designated OSM-Rβ. Heterodimeric receptor proteins comprising OSM-Rβ and gp130 bind oncostatin M and find use in inhibiting biological activities mediated by oncostatin M.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of application Ser. No. 08/308,881,filed Sep. 12, 1994, now U.S. Pat. No. 5,783,672, which is acontinuation-in-part of application Ser. No. 08/249,553, filed May 26,1994, now abandoned.

BACKGROUND OF THE INVENTION

Oncostatin M is a secreted single-chain polypeptide cytokine thatregulates the growth of certain tumor-derived and normal cell lines. Anumber of cell types have been found to bind the oncostatin M protein.See, for example, Linsley et al., J. Biol. Chem., 264: 4282 (1989).Oncostatin M has been shown to inhibit proliferation of a number oftumor cell types (Linsley et al. supra). In contrast, however, thisprotein has been implicated in stimulating proliferation of Kaposi'ssarcoma cells (Nair et al., Science 255:1430, 1992; Miles et al.,Science 255:1432, 1992; and Cai et al., Am. J. Pathol. 145:74, 1994).

Identifying and isolating oncostatin M-binding proteins, such as cellsurface oncostatin M receptors, is desirable for such reasons asenabling study of the biological signal transduced via the receptor.Such receptors in soluble form also could be used to competitivelyinhibit a biological activity of oncostatin M in various in vitro assaysor in vivo procedures. A soluble form of the receptor could beadministered to bind oncostatin M in vivo, thus inhibiting the bindingof oncostatin M to endogenous cell surface receptors, for example.

A protein known as gp130 has been found to bind oncostatin M, but withrelatively low affinity (Gearing et al., Science 255:1434, 1992).Heterodimeric receptors comprising a leukemia inhibitory factor (LIF)receptor and gp130 bind oncostatin M with higher affinity than doesgp130 alone, but also bind LIF with high affinity (Gearing et al.,supra). For certain applications, a receptor that binds oncostatin Mwith high affinity, but that does not function as a high affinity LIFreceptor, would be advantageous. Prior to the present invention, no suchreceptor had been identified or isolated.

SUMMARY OF THE INVENTION

The present invention provides a novel polypeptide that is designatedherein as the oncostatin M receptor β subunit (OSM-Rβ). Also provided isa receptor comprising OSM-Rβ linked (preferably covalently) to anoncostatin M-binding protein known as gp130. The gp130 polypeptide maybe covalently linked to the OSM-Rβ polypeptide by any suitable means,such as via a cross-linking reagent or a polypeptide linker. In oneembodiment of the invention, the receptor is a fusion protein producedby recombinant DNA technology. This receptor comprising OSM-Rβ and gp130binds oncostatin M at levels greater than does gp130 alone. Disordersmediated by oncostatin M may be treated by administering atherapeutically effective amount of this inventive receptor to a patientafflicted with such a disorder.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 presents a Scatchard analysis generated from an assay for bindingof radioiodinated oncostatin M by cells expressing recombinant gp130.The assay is described in example 2.

FIG. 2 presents a Scatchard analysis of the results of an assay forbinding of radioiodinated oncostatin M by cells expressing bothrecombinant gp130 and recombinant OSM-Rβ. As described in example 2, thedata in FIG. 2 demonstrate higher affinity oncostatin M binding comparedto the oncostatin M binding by gp130 alone depicted in FIG. 1.

FIG. 3 is a bar graph representing binding of leukemia inhibitory factor(LIF) and oncostatin M to various receptor proteins, as described inexample 5.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a novel polypeptide designated theoncostatin M receptor β subunit (OSM-Rβ). Isolated DNA encoding OSM-Rβ,expression vectors containing OSM-Rβ DNA, and host cells transformedwith such expression vectors are disclosed. Methods for production ofrecombinant OSM-Rβ polypeptides, including soluble forms of the protein,are also disclosed. Antibodies immunoreactive with the novel polypeptideare provided herein as well.

Another embodiment of the invention is directed to a receptor capable ofbinding oncostatin M, wherein the receptor comprises OSM-Rβ and gp130.The receptor finds use in various in vitro and in vivo procedures,including treatment of disorders mediated by oncostatin M.

DNA and encoded amino acid sequences of the OSM-Rβ cDNA isolated inexample 1 are presented in SEQ ID NO:5 and SEQ ID NO:6. The encodedprotein comprises (from N- to C-terminus) a signal peptide (amino acids-27 to -1 of SEQ ID NO:6) followed by an extracellular domain (aminoacids 1 to 714), a transmembrane region (amino acids 715 to 734) and acytoplasmic domain (amino acids 735 to 952). E. coli cells transformedwith a recombinant vector comprising OSM-Rβ cDNA in the cloning vectorpBluescript® SK⁻ were deposited with the American Type CultureCollection, Rockville, Md., U.S.A., on Aug. 16, 1994, and assignedaccession no. ATCC 69675.

The binding assay described in example 2 compared the binding ofoncostatin M by cells expressing either gp130 alone or both gp130 andOSM-Rβ. The cells expressing both gp130 and OSM-Rβ exhibited higheraffinity oncostatin M binding than did cells expressing gp130 alone. Theassay described in example 5 demonstrates that OSM-Rβ alone does notbind oncostatin M at a detectable level. However, proteins expressed bycells co-transfected with both a soluble OSM-Rβ/Fc fusionprotein-encoding vector and a soluble gp130/Fc fusion protein-encodingvector bound oncostatin M at higher levels than did proteins expressedby cells transfected with a soluble gp130/Fc-encoding vector alone.

In one embodiment, a receptor of the present invention comprises gp130covalently linked to OSM-Rβ by any suitable means, such as via across-linking reagent or a polypeptide linker. The gp130 and OSM-Rβproteins are covalently linked in a manner that does not interfere withthe resulting receptor's ability to bind oncostatin M. In oneembodiment, the receptor is a fusion protein produced by recombinant DNAtechnology.

Alternatively, the receptor may comprise gp130 non-covalently complexedwith OSM-Rβ. Non-covalent bonding of gp130 to OSM-Rβ may be achieved byany suitable means that does not interfere with the receptor's abilityto bind oncostatin M. In one approach, a first compound is attached toOSM-Rβ and a second compound that will non-covalently bond to the firstcompound is attached to gp130. Examples of such compounds are biotin andavidin. The receptor is thus formed through the non-covalentinteractions of biotin with avidin. In one embodiment of the invention,OSM-Rβ and gp130 are recombinant polypeptides, each purified fromrecombinant cells and then non-covalently bonded together to form thereceptor. A host cell may be transformed with two different expressionvectors such that both OSM-Rβ and gp130 are produced by the recombinanthost cell. OSM-Rβ and gp130 produced by such transformed host cells mayassociate to form a complex through non-covalent interactions. When suchtransformed cells express the membrane-bound forms of the proteins, suchcells are useful in various assays, including competition assays.

The protein designated gp130 herein has been purified from cellularsources that include placental tissue and a myeloma cell line U266. Anumber of additional cell types have been found to express gp130 mRNA,as reported by Hibi et al., in Cell 63:1149 (1990). gp130 has beenreported to be involved in the formation of high affinity interleukin-6binding sites and in IL-6 signal transduction (Hibi et al. supra). gp130also serves as an affinity converter for the LIF receptor (Gearing etal., Science 255:1434, 1992). The cloning and expression of cDNAencoding a full length gp130 protein has been reported by Hibi et al.,supra, which is hereby incorporated by reference in its entirety.

As used herein, the terms OSM-Rβ and gp130 include variants andtruncated forms of the native proteins that possess the desiredbiological activity. Variants produced by adding, substituting, ordeleting amino acid(s) in the native sequence are discussed in moredetail below.

One example of an OSM-Rβ polypeptide is that encoded by the cDNA clonedescribed in example 1 (i.e., encoded by the OSM-Rβ cDNA insert of therecombinant vector in deposited strain ATCC 69675). Other OSM-Rβpolypeptides include those lacking all or part of the transmembraneregion or the cytoplasmic domain of the protein. Additional truncatedOSM-Rβ polypeptides may be chosen with regard to sequences that areconserved in the hematopoietin receptor family. The desirability ofincluding the signal sequence depends on such factors as the position ofthe OSM-Rβ in a fusion protein and the intended host cells when thereceptor is to be produced via recombinant DNA technology.

One example of a suitable gp130 polypeptide is that comprising the aminoacid sequence presented in SEQ ID NO:2. E. coli strain DH5α cellstransformed with a gp130-encoding recombinant vector designatedB10G/pDC303 were deposited with the American Type Culture Collection,Rockville, Md., on Nov. 14, 1991, and assigned ATCC accession number68827. The mammalian expression vector pDC303 (into which the gp130 cDNAhas been inserted to form B10G/pDC303) is also known as SF CAV, and hasbeen described in PCT application WO 93/19777. The nucleotide sequenceof the gp130 cDNA contained in plasmid B10G/pDC303 and the amino acidsequence encoded thereby are presented in SEQ ID NO:1 and SEQ ID NO:2.The protein comprises (in order from the N-terminus to the C-terminus) a22-amino acid signal sequence, complete extracellular domain (aminoacids 1-597), a transmembrane region (beginning with amino acid 598),and a partial cytoplasmic domain (amino acids 621-686).

Alternatively, the gp130 protein disclosed by Hibi et al. supra may beemployed. The eighth amino acid of the signal peptide is valine in thesequence reported by Hibi et al., but is leucine in SEQ ID NO:2 (atposition -15). This difference in amino acid sequence may beattributable to genetic polymorphism (allelic variation amongindividuals producing the protein). In addition, the gp130 protein ofSEQ ID NO:2 is truncated within the cytoplasmic domain, terminating withthe leucine residue found at position 708 in the sequence presented inHibi et al. supra. Although truncated, the gp130 protein of SEQ ID NO:2comprises the extracellular domain responsible for oncostatin M binding,and thus is suitable for use as a component of the receptors of thepresent invention.

Regions of the gp130 protein corresponding to domains that are conservedamong certain receptors are discussed by Hibi et al, supra, at page1150, column 2, and page 1151, column 1. Other truncated gp130polypeptides chosen to include these conserved regions may be employed.

Soluble OSM-Rβ and gp130 polypeptides are preferred for certainapplications. In one embodiment of the present invention, the receptorcomprises soluble OSM-Rβ covalently attached to soluble gp130. "SolubleOSM-Rβ" as used in the context of the present invention refers topolypeptides that are substantially similar in amino acid sequence toall or part of the extracellular region of a native OSM-Rβ and that, dueto the lack of a transmembrane region that would cause retention of thepolypeptide on a cell membrane, are secreted upon expression. Suitablesoluble OSM-Rβ polypeptides retain the desired biological activity.Soluble OSM-Rβ may also include part of the transmembrane region or partof the cytoplasmic domain or other sequences, provided that the solubleOSM-Rβ protein is capable of being secreted.

Likewise, the term "soluble gp130" as used herein refers to proteinsthat are substantially similar in amino acid sequence to all or part ofthe extracellular region of a native gp130 and are secreted uponexpression but retain the desired biological activity. Soluble gp130 mayinclude part of the transmembrane region, cytoplasmic domain, or othersequences, as long as the polypeptide is secreted.

In one embodiment, soluble OSM-Rβ and gp130 polypeptides include theentire extracellular domain. To effect secretion, the solublepolypeptides comprise the native signal peptide or a heterologous signalpeptide. Thus, examples of soluble OSM-Rβ polypeptides comprise aminoacids -27 to 714 or 1 to 714 of SEQ ID NO:6. Examples of soluble gp130polypeptides comprise amino acids -22 to 597 or 1 to 597 of SEQ ID NO:2.

Additional examples of soluble gp130 polypeptides are those lacking fromone to all three of the fibronectin domains found within theextracellular domain, as described in example 4 below. These solublegp130 polypeptides include those comprising amino acids -22 to y or 1 toy of SEQ ID NO:2, wherein y is an integer between 308 and 597,inclusive.

A soluble fusion protein comprising amino acids -27 through 432 of theOSM-Rβ of SEQ ID NO:6 fused to an antibody Fc region polypeptide isdescribed in example 5. The OSM-Rβ moiety of the fusion protein, whichis a fragment of the OSM-Rβ extracellular domain, retained the desiredbiological activity. Thus, examples of soluble OSM-Rβ polypeptidescomprise amino acids -27 to x, or 1 to x of SEQ ID NO:6, wherein x is aninteger between 432 and 714, inclusive.

Soluble OSM-Rβ and soluble gp130 may be identified (and distinguishedfrom their non-soluble membrane-bound counterparts) by separating intactcells which express the desired protein from the culture medium, e.g.,by centrifugation, and assaying the medium (supernatant) for thepresence of the desired protein. The culture medium may be assayed usingprocedures which are similar or identical to those described in theexamples below. The presence of OSM-Rβ or gp130 in the medium indicatesthat the protein was secreted from the cells and thus is a soluble formof the desired protein. Soluble OSM-Rβ and soluble gp130 may benaturally-occurring forms of these proteins. Alternatively, solublefragments of OSM-Rβ and gp130 proteins may be produced by recombinantDNA technology or otherwise isolated, as described below.

The use of soluble forms of OSM-Rβ and gp130 is advantageous for certainapplications. Purification of the proteins from recombinant host cellsis facilitated, since the soluble proteins are secreted from the cells.Further, a receptor of the present invention comprising soluble OSM-Rβand gp130 proteins is generally more suitable for intravenousadministration.

With respect to the foregoing discussion of signal peptides and thevarious domains of the gp130 and OSM-Rβ proteins, the skilled artisanwill recognize that the above-described boundaries of such regions ofthe proteins are approximate. For example, although computer programsthat predict the site of cleavage of a signal peptide are available,cleavage can occur at sites other than those predicted. Further, it isrecognized that a protein preparation can comprise a mixture of proteinmolecules having different N-terminal amino acids, due to cleavage ofthe signal peptide at more than one site. In addition, the OSM-Rβtransmembrane region was identified by computer program prediction incombination with homology to the transmembrane region of the LIFreceptor protein described by Gearing et al. (EMBO J. 10:2839, 1991).Thus, soluble OSM-Rβ polypeptides comprising the extracellular domaininclude those having a C-terminal amino acid that may vary from thatidentified above as the C-terminus of the extracellular domain. Further,post-translational processing that can vary according to the particularexpression system employed may yield proteins having differingN-termini. Such variants that retain the desired biological activitiesare encompassed by the terms "OSM-Rβ polypeptides" and "gp130polypeptides" as used herein.

Truncated OSM-Rβ and gp130, including soluble polypeptides, may beprepared by any of a number of conventional techniques. In the case ofrecombinant proteins, a DNA fragment encoding a desired fragment may besubcloned into an expression vector. Alternatively, a desired DNAsequence may be chemically synthesized using known techniques. DNAfragments also may be produced by restriction endonuclease digestion ofa full length cloned DNA sequence, and isolated by electrophoresis onagarose gels. Linkers containing restriction endonuclease cleavagesite(s) may be employed to insert the desired DNA fragment into anexpression vector, or the fragment may be digested at cleavage sitesnaturally present therein. Oligonucleotides that reconstruct the N- orC-terminus of a DNA fragment to a desired point may be synthesized. Theoligonucleotide may contain a restriction endonuclease cleavage siteupstream of the desired coding sequence and position an initiation codon(ATG) at the N-terminus of the coding sequence.

The well known polymerase chain reaction procedure also may be employedto isolate a DNA sequence encoding a desired protein fragment.Oligonucleotide primers comprising the desired termini of the fragmentare employed in such a polymerase chain reaction. Any suitable PCRprocedure may be employed. One such procedure is described in Saiki etal., Science 239:487 (1988). Another is described in Recombinant DNAMethodology, Wu et al., eds., Academic Press Inc., San Diego (1989), pp.189-196. In general, PCR reactions involve combining the 5' and 3'oligonucleotide primers with template DNA (in this case, OSM-Rβ or gp130DNA) and each of the four deoxynucleoside triphosphates, in a suitablebuffered solution. The solution is heated, (e.g, from 95° to 100° C.) todenature the double-stranded DNA template and is then cooled beforeaddition of a DNA polymerase enzyme. Multiple cycles of the reactionsare carried out in order to amplify the desired DNA fragment.

The gp130 polypeptide is attached to the OSM-Rβ polypeptide through acovalent or non-covalent linkage. Covalent attachment is preferred forcertain applications, e.g. in vivo use, in view of the enhancedstability generally conferred by covalent, as opposed to non-covalent,bonds. In constructing the receptor of the present invention, covalentlinkage may be accomplished via cross-linking reagents, peptide linkers,or any other suitable technique.

Numerous reagents useful for cross-linking one protein molecule toanother are known. Heterobifunctional and homobifunctional linkers areavailable for this purpose from Pierce Chemical Company, Rockford, Ill.,for example. Such linkers contain two functional groups (e.g., estersand/or maleimides) that will react with certain functional groups onamino acid side chains, thus linking one polypeptide to another.

One type of peptide linker that may be employed in the present inventionseparates gp130 and OSM-Rβ domains by a distance sufficient to ensurethat each domain properly folds into the secondary and tertiarystructures necessary for the desired biological activity. The linkeralso should allow the extracellular domains of gp130 and OSM-Rβ toassume the proper spatial orientation to form the binding site foroncostatin M.

Suitable peptide linkers are known in the art, and may be employedaccording to conventional techniques. Among the suitable peptide linkersare those described in U.S. Pat. Nos. 4,751,180 and 4,935,233, which arehereby incorporated by reference. A peptide linker may be attached togp130 and to OSM-Rβ by any of the conventional procedures used to attachone polypeptide to another. The cross-linking reagents available fromPierce Chemical Company as described above are among those that may beemployed. Amino acids having side chains reactive with such reagents maybe included in the peptide linker, e.g., at the termini thereof.Preferably, a fusion protein comprising gp130 joined to OSM-Rβ via apeptide linker is prepared by recombinant DNA technology.

In one embodiment of the invention, OSM-Rβ and gp130 are linked viapolypeptides derived from immunoglobulins. Preparation of fusionproteins comprising heterologous polypeptides fused to various portionsof antibody-derived polypeptides (including the Fc domain) has beendescribed, e.g., by Ashkenazi et al. (PNAS USA 88:10535, 1991) and Byrnet al. (Nature 344:677, 1990). As one example, a polypeptide derivedfrom the Fc region of an antibody may be attached to the C-terminus ofOSM-Rβ. A separate Fc polypeptide is attached to the C-terminus ofgp130. Disulfide bonds form between the two Fc polypeptides (e.g., inthe so-called hinge region, where interchain disulfide bonds arenormally present in antibody molecules), producing a heterodimercomprising the gp130 and to OSM-Rβ/Fc fusion protein linked to thegp130/Fc fusion protein. Advantageously, host cells are co-transfectedwith two different expression vectors, one encoding soluble OSM-Rβ/Fcand the other encoding soluble gp130/Fc. The heterodimer is believed toform intracellularly or during secretion.

The term "Fc polypeptide" as used herein includes native and muteinforms, as well as truncated Fc polypeptides containing the hinge regionthat promotes dimerization. cDNA encoding a single chain polypeptidederived from the Fc region of a human IgG1 antibody has been cloned intothe pBluescript SK® cloning vector (Stratagene Cloning Systems, LaJolla,Calif.) to produce a recombinant vector designated hIgG1Fc. A uniqueBglII site is positioned near the 5' end of the inserted Fc encodingsequence. An SpeI site is immediately downstream of the stop codon. TheDNA and encoded amino acid sequences of the cloned Fc cDNA are presentedin SEQ ID NO:3 and SEQ ID NO:4. The Fc polypeptide encoded by the cDNAextends from the N-terminal hinge region to the native C-terminus, i.e.,is an essentially full-length antibody Fc region. One suitable mutein ofthis Fc polypeptide is described in U.S. Pat. No. 5,457,035, herebyincorporated by reference. The mutein exhibits reduced affinity for Fcreceptors.

Homodimers comprising two OSM-Rβ/Fc polypeptides or two gp130/Fcpolypeptides linked via disulfide bonds are also produced by certain ofthe transfected host cells disclosed herein. The homodimers may beseparated from each other and from the heterodimer by virtue ofdifferences in size (e.g., by gel electrophoresis). The heterodimer alsomay be purified by sequential immunoaffinity chromatography (describedbelow).

In an alternative embodiment, a first fusion polypeptide comprisinggp130 (or a fragment thereof) upstream of the constant region of anantibody light chain (or a fragment thereof) is prepared. A secondfusion polypeptide comprises OSM-Rβ upstream of the constant region ofan antibody heavy chain (or a heavy chain fragment, the N-terminus ofwhich extends at least through the C_(H).spsb.1 region. Disulfidebond(s) form between the gp130-light chain fusion polypeptide and theOSM-Rβ-heavy chain fusion polypeptide, thus producing a receptor of thepresent invention. As a further alternative, an OSM-Rβ-antibody lightchain fusion polypeptide is prepared and combined with (disulfide bondedto) a fusion polypeptide comprising gp130 fused to an antibody heavychain. When two of the foregoing disulfide bonded molecules arecombined, additional disulfide bonds form between the two Fc regions.The resulting receptor of the present invention comprising four fusionpolypeptides resembles an antibody in structure and displays theoncostatin M binding site bivalently.

The gp130 and OSM-Rβ polypeptides may be separately purified fromcellular sources, and then linked together. Alternatively, the receptorof the present invention may be produced using recombinant DNAtechnology. The gp130 and OSM-Rβ polypeptides may be produced separatelyand purified from transformed host cells for subsequent covalentlinkage. In one embodiment of the present invention, a host cell istransformed/transfected with foreign DNA that encodes gp130 and OSM-Rβas separate polypeptides. The two polypeptides may be encoded by thesame expression vector with start and stop codons for each of the twogenes, or the recombinant cells may be co-transfected with two separateexpression vectors. In another embodiment, the receptor is produced as afusion protein in recombinant cells.

In one embodiment of the present invention, the receptor protein is arecombinant fusion protein of the formula:

    R.sub.1 -L-R.sub.2 or R.sub.2 -L-R.sub.1

wherein R₁ represents gp130 or a gp130 fragment; R₂ represents OSM-Rβ oran OSM-Rβ fragment; and L represents a peptide linker.

The fusion proteins of the present invention include constructs in whichthe C-terminal portion of gp130 is fused to the linker which is fused tothe N-terminal portion of OSM-Rβ, and also constructs in which theC-terminal portion of OSM-Rβ is fused to the linker which is fused tothe N-terminal portion of gp130. gp130 is covalently linked to OSM-Rβ insuch a manner as to produce a single protein which retains the desiredbiological activities of gp130 and OSM-Rβ. The components of the fusionprotein are listed in their order of occurrence (i.e., the N-terminalpolypeptide is listed first, followed by the linker and then theC-terminal polypeptide).

A DNA sequence encoding a fusion protein is constructed usingrecombinant DNA techniques to insert separate DNA fragments encodinggp130 and OSM-Rβ into an appropriate expression vector. The 3' end of aDNA fragment encoding gp130 is ligated (via the linker) to the 5' end ofthe DNA fragment encoding OSM-Rβ with the reading frames of thesequences in phase to permit translation of the mRNA into a singlebiologically active fusion protein. Alternatively, the 3' end of a DNAfragment encoding OSM-Rβ may be ligated (via the linker) to the 5' endof the DNA fragment encoding gp130, with the reading frames of thesequences in phase to permit translation of the mRNA into a singlebiologically active fusion protein. A DNA sequence encoding anN-terminal signal sequence may be retained on the DNA sequence encodingthe N-terminal polypeptide, while stop codons, which would preventread-through to the second (C-terminal) DNA sequence, are eliminated.Conversely, a stop codon required to end translation is retained on thesecond DNA sequence. DNA encoding a signal sequence is preferablyremoved from the DNA sequence encoding the C-terminal polypeptide.

A DNA sequence encoding a desired polypeptide linker may be insertedbetween, and in the same reading frame as, the DNA sequences encodinggp130 and OSM-Rβ using any suitable conventional technique. For example,a chemically synthesized oligonucleotide encoding the linker andcontaining appropriate restriction endonuclease cleavage sites may beligated between the sequences encoding gp130 and OSM-Rβ.

Alternatively, a chemically synthesized DNA sequence may contain asequence complementary to the 3' terminus (without the stop codon) ofeither gp130 or OSM-Rβ, followed by a linker-encoding sequence which isfollowed by a sequence complementary to the 5' terminus of the other ofgp130 and OSM-Rβ. Oligonucleotide directed mutagenesis is then employedto insert the linker-encoding sequence into a vector containing a directfusion of gp130 and OSM-Rβ.

The present invention provides isolated DNA sequences encoding theabove-described fusion proteins comprising gp130, OSM-Rβ, and a peptidelinker. DNA encoding the novel OSM-Rβ polypeptides disclosed herein isalso provided, as is DNA encoding OSM-Rβ polypeptides fused toimmunoglobin-derived polypeptides. OSM-Rβ-encoding DNA encompassed bythe present invention includes, for example, cDNA, chemicallysynthesized DNA, DNA isolated by PCR, genomic DNA, and combinationsthereof. Genomic OSM-Rβ DNA may be isolated using the cDNA isolated inExample 1, or fragments thereof, as a probe using standard techniques.

Also provided herein are recombinant expression vectors containing theisolated DNA sequences. "Expression vector" refers to a replicable DNAconstruct used to express DNA which encodes the desired protein andwhich includes a transcriptional unit comprising an assembly of (1)genetic element(s) having a regulatory role in gene expression, forexample, promoters, operators, or enhancers, operatively linked to (2) aDNA sequence encoding a desired protein which is transcribed into mRNAand translated into protein, and (3) appropriate transcription andtranslation initiation and termination sequences. The choice of promoterand other regulatory elements generally varies according to the intendedhost cell.

In the expression vectors, regulatory elements controlling transcriptionor translation are generally derived from mammalian, microbial, viral orinsect genes. The ability to replicate in a host, usually conferred byan origin of replication, and a selection gene to facilitate recognitionof transformants may additionally be incorporated. Vectors derived fromretroviruses also may be employed.

DNA regions are operably linked when they are functionally related toeach other. For example, DNA encoding a signal peptide (secretoryleader) is operably linked to DNA for a polypeptide if the polypeptideis expressed as a precursor that is secreted through the host cellmembrane; a promoter is operably linked to a coding sequence if itcontrols the transcription of the sequence; and a ribosome binding siteis operably linked to a coding sequence if it is positioned so as topermit translation. Generally, "operably linked" means contiguous and,in the case of secretory leaders, contiguous and in reading frame.

Transformed host cells are cells which have been transformed ortransfected with foreign DNA using recombinant DNA techniques. In thecontext of the present invention, the foreign DNA includes a sequenceencoding the inventive proteins. Host cells may be transformed forpurposes of cloning or amplifying the foreign DNA, or may be transformedwith an expression vector for production of the protein. Suitable hostcells include prokaryotes, yeast or higher eukaryotic cells. Appropriatecloning and expression vectors for use with bacterial, fungal, yeast,and mammalian cellular hosts are described by Pouwels et al. (CloningVectors: A Laboratory Manual, Elsevier, N.Y., 1985), the relevantdisclosure of which is hereby incorporated by reference.

Prokaryotes include gram negative or gram positive organisms, forexample E. coli or bacilli. Prokaryotic expression vectors generallycomprise one or more phenotypic selectable markers, for example a geneencoding proteins conferring antibiotic resistance or supplying anautotrophic requirement, and an origin of replication recognized by thehost to ensure amplification within the host. Examples of suitableprokaryotic hosts for transformation include E. coli, Bacillus subtilis,Salmonella typhimurium, and various species within the generaPseudomonas, Streptomyces, and Staphylococcus, although others may alsobe employed as a matter of choice.

Useful expression vectors for bacterial use can comprise a selectablemarker and bacterial origin of replication derived from commerciallyavailable plasmids comprising genetic elements of the well-known cloningvector pBR322 (ATCC 37017). Such commercial vectors include, forexample, pKK223-3 (Pharmacia Fine Chemicals, Uppsala, Sweden) and pGEM1(Promega Biotec, Madison, Wis., USA). These pBR322 "backbone" sectionsare combined with an appropriate promoter and the structural sequence tobe expressed. E. coli is typically transformed using derivatives ofpBR322, a plasmid derived from an E. coli species (Bolivar et al., Gene2:95, 1977). pBR322 contains genes for ampicillin and tetracyclineresistance and this provides simple means for identifying transformedcells.

Promoters commonly used in recombinant microbial expression vectorsinclude the β-lactamase (penicillinase) and lactose promoter system(Chang et al., Nature 275:615, 1978; and Goeddel et al., Nature 281:544,1979), the tryptophan (trp) promoter system (Goeddel et al., Nucl. AcidsRes. 8:4057, 1980; and EPA 36,776) and tac promoter (Maniatis, MolecularCloning: A Laboratory Manual, Cold Spring Harbor Laboratory, p. 412,1982). A particularly useful bacterial expression system employs thephage λ P_(L) promoter and cI857ts thermoinducible repressor. Plasmidvectors available from the American Type Culture Collection whichincorporate derivatives of the λ P_(L) promoter include plasmid pHUB2,resident in E. coli strain JMB9 (ATCC 37092) and pPLc28, resident in E.coli RR1 (ATCC 53082).

The recombinant receptor protein may also be expressed in yeast hosts,preferably from Saccharomyces species, such as S. cerevisiae. Yeast ofother genera such as Pichia or Kluyveromyces may also be employed. Yeastvectors will generally contain an origin of replication from the 2 μmyeast plasmid or an autonomously replicating sequence (ARS), a promoter,DNA encoding the receptor fusion protein, sequences for polyadenylationand transcription termination and a selection gene. Preferably, yeastvectors will include an origin of replication and selectable markerspermitting transformation of both yeast and E. coli, e.g., theampicillin resistance gene of E. coli and the S. cerevisiae trp1 gene,which provides a selection marker for a mutant strain of yeast lackingthe ability to grow in tryptophan, and a promoter derived from a highlyexpressed yeast gene to induce transcription of a structural sequencedownstream. The presence of the trp1 lesion in the yeast host cellgenome then provides an effective environment for detectingtransformation by growth in the absence of tryptophan.

Suitable promoter sequences in yeast vectors include the promoters formetallothionein, 3-phosphoglycerate kinase (Hitzeman et al., J. Biol.Chem. 255:2073, 1980) or other glycolytic enzymes (Hess et al., J. Adv.Enzyme Reg. 7:149, 1968; and Holland et al., Biochem. 17:4900, 1978),such as enolase, glyceraldehyde-3-phosphate dehydrogenase, hexokinase,pyruvate decarboxylase, phosphofructokinase, glucose-6-phosphateisomerase, 3-phosphoglycerate mutase, pyruvate kinase, triosephosphateisomerase, phosphoglucose isomerase and glucokinase. Suitable vectorsand promoters for use in yeast expression are further described in R.Hitzeman et al., EPA 73,657.

Preferred yeast vectors can be assembled using DNA sequences from pBR322for selection and replication in E. coli (Amp^(r) gene and origin ofreplication) and yeast DNA sequences including a glucose-repressibleADH2 promoter and α-factor secretion leader. The ADH2 promoter has beendescribed by Russell et al. (J. Biol. Chem. 258:2674, 1982) and Beier etal., (Nature 300:724, 1982). The yeast α-factor leader, which directssecretion of heterologous proteins, can be inserted between the promoterand the structural gene to be expressed. See, e.g., Kurjan et al., Cell30:922, 1982; and Bitter et al., Proc. Natl. Acad. Sci. USA 81:5330,1984. The leader sequence may be modified to contain, near its 3' end,one or more useful restriction sites to facilitate fusion of the leadersequence to foreign genes.

Suitable yeast transformation protocols are known to those of skill inthe art. An exemplary technique is described by Hinnen et al., Proc.Natl. Acad. Sci. USA 75:1929, (1978), selecting for Trp⁺ transformantsin a selective medium consisting of 0.67% yeast nitrogen base, 0.5%casamino acids, 2% glucose, 10 μg/ml adenine and 20 μg/ml uracil.

Host strains transformed by vectors comprising the ADH2 promoter may begrown for expression in a rich medium consisting of 1% yeast extract, 2%peptone, and 1% glucose supplemented with 80 μg/ml adenine and 80 μg/mluracil. Derepression of the ADH2 promoter occurs upon exhaustion ofmedium glucose. Crude yeast supernatants are harvested by filtration andheld at 4° C. prior to further purification.

Various mammalian or insect cell culture systems can be employed toexpress recombinant protein. Baculovirus systems for production ofheterologous proteins in insect cells are reviewed by Luckow andSummers, Bio/Technology 6:47 (1988). Examples of suitable mammalian hostcell lines include L cells, C127, 3T3, Chinese hamster ovary (CHO),HeLa, and BHK cell lines. Additional suitable mammalian host cellsinclude CV-1 cells (ATCC CCL70) and COS-7 cells (ATCC CRL 1651;described by Gluzman, Cell 23:175, 1981), both derived from monkeykidney. Another monkey kidney cell line, CV-1/EBNA (ATCC CRL 10478), wasderived by transfection of the CV-1 cell line with a gene encodingEpstein-Barr virus nuclear antigen-1 (EBNA-1) and with a vectorcontaining CMV regulatory sequences (McMahan et al., EMBO J. 10:2821,1991). The EBNA-1 gene allows for episomal replication of expressionvectors, such as HAV-EO or pDC406, that contain the EBV origin ofreplication.

Mammalian expression vectors may comprise non-transcribed elements suchas an origin of replication, a suitable promoter and enhancer linked tothe gene to be expressed, and other 5' or 3' flanking nontranscribedsequences, and 5' or 3' nontranslated sequences, such as necessaryribosome binding sites, a poly-adenylation site, splice donor andacceptor sites, and transcriptional termination sequences. Thetranscriptional and translational control sequences in expressionvectors to be used in transforming vertebrate cells may be provided byviral sources. For example, commonly used promoters and enhancers arederived from Polyoma, Adenovirus 2, Simian Virus 40 (SV40), and humancytomegalovirus. DNA sequences derived from the SV40 viral genome, forexample, SV40 origin, early and late promoter, enhancer, splice, andpolyadenylation sites may be used to provide the other genetic elementsrequired for expression of a heterologous DNA sequence. The early andlate promoters are particularly useful because both are obtained easilyfrom the virus as a fragment which also contains the SV40 viral originor replication (Fiers et al., Nature 273:113, 1978). Smaller or largerSV40 fragments may also be used, provided the approximately 250 bpsequence extending from the Hind III site toward the BglI site locatedin the viral origin of replication is included.

Exemplary vectors can be constructed as disclosed by Okayama and Berg(Mol. Cell. Biol. 3:280, 1983). One useful system for stable high levelexpression of mammalian receptor cDNAs in C127 murine mammary epithelialcells can be constructed substantially as described by Cosman et al.(Mol. Immnunol. 23:935, 1986). Vectors derived from retroviruses alsomay be employed.

When secretion of the OSM-Rβ protein from the host cell is desired, theexpression vector may comprise DNA encoding a signal or leader peptide.In place of the native signal sequence, a heterologous signal sequencemay be added, such as the signal sequence for interleukin-7 (IL-7)described in U.S. Pat. No. 4,965,195; the signal sequence forinterleukin-2 receptor described in Cosman et al., Nature 312:768(1984); the interleukin-4 signal peptide described in EP 367,566; thetype I interleukin-1 receptor signal peptide described in U.S. Pat. No.4,968,607; and the type II interleukin-1 receptor signal peptidedescribed in EP 460,846.

The present invention provides a process for preparing the recombinantproteins of the present invention, comprising culturing a host celltransformed with an expression vector comprising a DNA sequence thatencodes said protein under conditions that promote expression. Thedesired protein is then purified from culture media or cell extracts.The desired protein may be OSM-Rβ or the heterodimeric receptor, forexample. Cell-free translation systems could also be employed to producethe desired protein using RNA derived from the novel DNA of the presentinvention.

As one example, supernatants from expression systems that secreterecombinant protein into the culture medium can be first concentratedusing a commercially available protein concentration filter, forexample, an Amicon or Millipore Pellicon ultrafiltration unit. Followingthe concentration step, the concentrate can be applied to a suitablepurification matrix. For example, a suitable affinity matrix cancomprise oncostatin M. An oncostatin M affinity matrix may be preparedby coupling recombinant human oncostatin M to cyanogen bromide-activatedSepharose (Pharmacia) or Hydrazide Affigel (Biorad), according tomanufacturer's recommendations. Sequential immunopurification usingantibodies bound to a suitable support is preferred. Proteins binding toan antibody specific for OSM-Rβ are recovered and contacted withantibody specific for gp130 on an insoluble support. Proteinsimmunoreactive with both antibodies may thus be identified and isolated.

Alternatively, an anion exchange resin can be employed, for example, amatrix or substrate having pendant diethylaminoethyl (DEAE) groups. Thematrices can be acrylamide, agarose, dextran, cellulose or other typescommonly employed in protein purification. Alternatively, a cationexchange step can be employed. Suitable cation exchangers includevarious insoluble matrices comprising sulfopropyl or carboxymethylgroups. Sulfopropyl groups are preferred. One or more reversed-phasehigh performance liquid chromatography (RP-HPLC) steps employinghydrophobic RP-HPLC media, e.g., silica gel having pendant methyl orother aliphatic groups, can be employed to further purify a fusionprotein.

Some or all of the foregoing purification steps, in variouscombinations, can be employed to provide an essentially homogeneousrecombinant protein. Recombinant cell culture enables the production ofthe fusion protein free of those contaminating proteins which may benormally associated with gp130 or OSM-Rβ as they are found in nature intheir respective species of origin, e.g., on the surface of certain celltypes.

The foregoing purification procedures are among those that may beemployed to purify non-recombinant receptors of the present invention aswell. When linking procedures that may produce homodimers(gp130-linker-gp130 and OSM-Rβ-linker-OSM-Rβ) are employed, purificationprocedures that separate the heterodimer from such homodimers areemployed. An example of such a procedure is sequentialimmunopurification as discussed above. In one embodiment, OSM-Rβ(recombinant or non-recombinant) is purified such that no bandscorresponding to other (contaminating) proteins are detectable bySDS-PAGE.

Recombinant protein produced in bacterial culture is usually isolated byinitial extraction from cell pellets, followed by one or moreconcentration, salting-out, aqueous ion exchange or size exclusionchromatography steps. Finally, high performance liquid chromatography(HPLC) can be employed for final purification steps. Microbial cellsemployed in expression of recombinant fusion proteins can disrupted byany convenient method, including freeze-thaw cycling, sonication,mechanical disruption, or use of cell lysing agents.

Fermentation of yeast which express fusion proteins as a secretedprotein greatly simplifies purification. Secreted recombinant proteinresulting from a large-scale fermentation can be purified by methodsanalogous to those disclosed by Urdal et al. (J. Chromatog. 296:171,1984), involving two sequential, reversed-phase HPLC steps forpurification of a recombinant protein on a preparative HPLC column.

The DNA or amino acid sequences of gp130 and OSM-Rβ may vary from thosepresented in SEQ ID NO:1 and SEQ ID NO:5, respectively. Due to the knowndegeneracy of the genetic code, there can be considerable variation innucleotide sequences encoding the same amino acid sequence. In addition,DNA sequences capable of hybridizing to the native DNA sequence of SEQID NO:1 or SEQ ID NO:5 under moderately stringent or highly stringentconditions, and which encode a biologically active gp130 or OSM-Rβpolypeptide, respectively, are also considered to be gp130-encoding orOSM-Rβ-encoding DNA sequences, in the context of the present invention.Such hybridizing sequences include but are not limited to variantsequences such as those described below, and DNA derived from othermammalian species. Human OSM-Rβ is within the scope of the presentinvention, as are OSM-Rβ proteins derived from other mammalian species,including but not limited to rat, bovine, porcine, or various non-humanprimates.

Moderately stingent conditions include conditions described in, forexample, Sambrook et al, Molecular Cloning: A Laboratory Manual, 2nded., Vol. 1, pp 1.101-104, Cold Spring Harbor Laboratory Press, 1989.Conditions of moderate stingency, as defined by Sambrook et al., includeuse of a prewashing solution of 5× SSC, 0.5% SDS, 1.0 mM EDTA (pH 8.0)and hybridization conditions of about 55° C., 5× SSC, overnight. Highlystringent conditions include higher temperatures of hybridization andwashing. The skilled artisan will recognize that the temperature andwash solution salt concentration may be adjusted as necessary accordingto factors such as the length of the probe. One embodiment of theinvention is directed to DNA sequences that will hybridize to the OSM-RβDNA of SEQ ID NO:5 under highly stringent conditions, wherein saidconditions include hybridization at 68° C. followed by washing in 0.1×SSC/0.1% SDS at 63-68° C. In another embodiment, the present inventionprovides a heterodimeric receptor comprising OSM-Rβ and gp130, whereinsaid OSM-Rβ and gp130 are encoded by DNA that hybridizes to the DNA ofSEQ ID NO:5 or SEQ ID NO:1, respectively, under moderately or highlystringent conditions.

Further, certain mutations in a nucleotide sequence which encodes OSM-Rβor gp130 will not be expressed in the final protein product. Forexample, nucleotide substitutions may be made to enhance expression,primarily to avoid secondary structure loops in the transcribed mRNA(see EP 75,444A). Other alterations of the nucleotide sequence may bemade to provide codons that are more readily translated by the selectedhost, e.g., the well-known E. coli preference codons for E. coliexpression.

The amino acid sequence of native gp130 or OSM-Rβ may be varied bysubstituting, deleting, adding, or inserting one or more amino acids toproduce a gp130 or OSM-Rβ variant. Variants that possess the desiredbiological activity of the native gp130 and OSM-Rβ proteins may beemployed in the receptor of the present invention. Assays by which thebiological activity of variant proteins may be analyzed are described inthe examples below. Biologically active gp130 polypeptides are capableof binding oncostatin M. The desired biological activity of the OSM-Rβpolypeptides disclosed herein is the ability to enhance the binding ofoncostatin M when OSM-Rβ is joined to gp130, compared to the level ofoncostatin M binding to gp130 alone.

Alterations to the native amino acid sequence may be accomplished by anyof a number of known techniques. For example, mutations can beintroduced at particular loci by synthesizing oligonucleotidescontaining a mutant sequence, flanked by restriction sites enablingligation to fragments of the native sequence. Following ligation, theresulting reconstructed sequence encodes an analog having the desiredamino acid insertion, substitution, or deletion.

Alternatively, oligonucleotide-directed site-specific mutagenesisprocedures can be employed to provide an altered gene having particularcodons altered according to the substitution, deletion, or insertionrequired. Exemplary methods of making the alterations set forth aboveare disclosed by Walder et al. (Gene 42:133, 1986); Bauer et al. (Gene37:73, 1985); Craig (BioTechniques, January 1985, 12-19); Smith et al.(Genetic Engineering: Principles and Methods, Plenum Press, 1981); U.S.Pat. No. 4,518,584, and U.S. Pat. No. 4,737,462, which are incorporatedby reference herein.

Bioequivalent variants of OSM-Rβ and gp130 may be constructed by, forexample, making various substitutions of amino acid residues or deletingterminal or internal amino acids not needed for biological activity. Inone embodiment of the invention, the variant amino acid sequence is atleast 80% identical, preferably at least 90% identical, to the nativesequence. Percent similarity may be determined, for example, bycomparing sequence information using the GAP computer program, version6.0, available from the University of Wisconsin Genetics Computer Group(UWGCG). The GAP program utilizes the alignment method of Needleman andWunsch (J. Mol. Biol. 48:443, 1970), as revised by Smith and Waterman(Adv. Appl. Math. 2:482, 1981). Briefly, the GAP program definessimilarity as the number of aligned symbols (i.e., nucleotides or aminoacids) which are similar, divided by the total number of symbols in theshorter of the two sequences. The preferred default parameters for theGAP program include: (1) a unary comparison matrix (containing a valueof 1 for identities and 0 for non-identities) for nucleotides, and theweighted comparison matrix of Gribskov and Burgess, Nucl. Acids Res.14:6745, 1986, as described by Schwartz and Dayhoff, eds., Atlas ofProtein Sequence and Structure, National Biomedical Research Foundation,pp. 353-358, 1979; (2) a penalty of 3.0 for each gap and an additional0.10 penalty for each symbol in each gap; and (3) no penalty for endgaps.

Generally, substitutions should be made conservatively; i.e., the mostpreferred substitute amino acids are those having physiochemicalcharacteristics resembling those of the residue to be replaced. Examplesof conservative substitutions include substitution of one aliphaticresidue for another, such as Ile, Val, Leu, or Ala for one another, orsubstitutions of one polar residue for another, such as between Lys andArg; Glu and Asp; or Gln and Asn. Other such conservative substitutions,for example, substitutions of entire regions having similarhydrophobicity characteristics, are well known.

Cysteine residues can be deleted or replaced with other amino acids toprevent formation of unnecessary or incorrect intramolecular disulfidebridges upon renaturation. Hydrophilic amino acids may be substitutedfor hydrophobic amino acids in the transmembrane region and/orintracellular domain of gp130 and OSM-Rβ to enhance water solubility ofthe proteins.

Adjacent dibasic amino acid residues may be modified to enhanceexpression in yeast systems in which KEX2 protease activity is present.EP 212,914 discloses the use of site-specific mutagenesis to inactivateKEX2 protease processing sites in a protein. KEX2 protease processingsites are inactivated by deleting, adding or substituting residues toalter Arg-Arg, Arg-Lys, and Lys-Arg pairs to eliminate the occurrence ofthese adjacent basic residues. These amino acid pairs, which constituteKEX2 proteases processing sites, are found at residues 290-291, 291-292,580-581, and 797-798 of the OSM-Rβ protein of SEQ ID NO:6. These KEX2sites are found at positions 153-154 and 621-622 of the gp130 protein ofSEQ ID NO:2. Lys-Lys pairings are considerably less susceptible to KEX2cleavage, and conversion of Arg-Lys or Lys-Arg to Lys-Lys represents aconservative and preferred approach to inactivating KEX2 sites.

The present invention also includes proteins with or without associatednative-pattern glycosylation. Expression of DNAs encoding the fusionproteins in bacteria such as E. coli provides non-glycosylatedmolecules. Functional mutant analogs having inactivated N-glycosylationsites can be produced by oligonucleotide synthesis and ligation or bysite-specific mutagenesis techniques. These analog proteins can beproduced in a homogeneous, reduced-carbohydrate form in good yield usingyeast expression systems. N-glycosylation sites in eukaryotic proteinsare characterized by the amino acid triplet Asn-A₁ -Z, where A1 is anyamino acid except Pro, and Z is Ser or Thr. In this sequence, asparagineprovides a side chain amino group for covalent attachment ofcarbohydrate.

The OSM-Rβ amino acid sequence in SEQ ID NO:6 contains 16 suchN-glycosylation sites, all found in the extracellular domain, at aminoacids 15-17, 57-59, 104-106, 136-138, 149-151, 194-196, 280-282,299-301, 318-320, 334-336, 353-355, 395-397, 419-421, 464-466, 482-484,and 553-555 of SEQ ID NO:6. The extracellular domain of gp130 comprisesN-glycosylation sites at positions 21-23, 61-63, 109-111, 135-137,205-207, 224-226, 357-359, 361-363, 368-370, 531-533, and 542-544 of SEQID NO:2. Such a site can be eliminated by substituting another aminoacid for Asn or for residue Z, deleting Asn or Z, or inserting a non-Zamino acid between A₁ and Z, or an amino acid other than Asn between Asnand A₁. Known procedures for inactivating N-glycosylation sites inproteins include those described in U.S. Pat. No. 5,071,972 and EP276,846.

Variants of the receptor proteins of the present invention also includevarious structural forms of the primary protein which retain biologicalactivity. Due to the presence of ionizable amino and carboxyl groups,for example, a receptor protein may be in the form of acidic or basicsalts, or may be in neutral form. Individual amino acid residues mayalso be modified by oxidation or reduction.

The primary amino acid structure also may be modified by formingcovalent or aggregative conjugates with other chemical moieties, such asglycosyl groups, lipids, phosphate, acetyl groups and the like. Covalentderivatives are prepared by linking particular functional groups toamino acid side chains or at the N- or C-termini. Other derivatives ofthe receptor protein within the scope of this invention include covalentor aggregative conjugates of the receptor protein with other proteins orpolypeptides, such as by synthesis in recombinant culture as N- orC-terminal fusions. For example, the conjugated polypeptide may be asignal (or leader) polypeptide sequence at the N-terminal region of theprotein which co-translationally or post-translationally directstransfer of the protein from its site of synthesis to its site offunction inside or outside of the cell membrane or wall (e.g., the yeastα-factor leader).

Peptides may be fused to the desired protein (e.g., via recombinant DNAtechniques) to facilitate purification or identification. Examplesinclude poly-His or the Flag® peptide Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys(SEQ ID NO:7) (Hopp et al., Bio/Technology 6:1204, 1988, and U.S. Pat.No. 5,011,912). The Flag® peptide is highly antigenic and provides anepitope reversibly bound by a specific monoclonal antibody, enablingrapid assay and facile purification of expressed recombinant protein.Expression systems useful for fusing the Flag® octapeptide to the N- orC-terminus of a given protein are available from Eastman Kodak Co.,Scientific Imaging Systems Division, New Haven, Conn., as are monoclonalantibodies that bind the octapeptide.

Encompassed by the present invention are OSM-Rβ polypeptides in the formof oligomers, such as dimers or trimers. Such oligomers may be naturallyoccurring or produced by recombinant DNA technology. The presentinvention provides oligomers of OSM-Rβ (preferably the extracellulardomain or a fragment thereof), linked by disulfide bonds or expressed asfusion proteins with or without peptide linkers. Oligomers may be formedby disulfide bonds between cysteine residues on different OSM-Rβpolypeptides, for example. In another embodiment, OSM-Rβ oligomers maybe prepared using polypeptides derived from immunoglobulins, asdescribed above.

Naturally occurring OSM-Rβ variants are also encompassed by the presentinvention. Examples of such variants are proteins that result fromalternative mRNA splicing events or from proteolytic cleavage of theOSM-Rβ protein, wherein the desired biological activity is retained.Alternative splicing of mRNA may yield a truncated but biologicallyactive OSM-Rβ protein, such as a naturally occurring soluble form of theprotein, for example. Variations attributable to proteolysis include,for example, differences in the N- or C-termini upon expression indifferent types of host cells, due to proteolytic removal of one or moreterminal amino acids from the OSM-Rβ protein (generally from 1-5terminal amino acids). Naturally occurring gp130 variants may beemployed in the inventive receptors.

The present invention also provides a pharmaceutical compositioncomprising a receptor protein of the present invention with aphysiologically acceptable carrier or diluent. Such carriers anddiluents will be nontoxic to recipients at the dosages andconcentrations employed. Such compositions may, for example, comprisethe receptor protein in a buffered solution, to which may be addedantioxidants such as ascorbic acid, low molecular weight (less thanabout ten residues) polypeptides, proteins, amino acids, carbohydratesincluding glucose, sucrose or dextrins, chelating agents such as EDTA,glutathione and other stabilizers and excipients. The receptor of thepresent invention may be administered by any suitable method in a mannerappropriate to the indication, such as intravenous injection, localadministration, continuous infusion, sustained release from implants,etc.

The heterodimeric receptor of the present invention (comprising gp130and OSM-Rβ) is useful as an oncostatin M binding reagent. This receptor,which preferably comprises soluble gp130 and soluble OSM-Rβ, hasapplications both in vitro and in vivo. The receptors may be employed inin vitro assays, e.g., in studies of the mechanism of transduction ofthe biological signal that is initiated by binding of oncostatin M tothis receptor on a cell. Such receptors also could be used to inhibit abiological activity of oncostatin M in various in vitro assays or invivo procedures. In one embodiment of the invention, the inventivereceptor is administered to bind oncostatin M, thus inhibiting bindingof the oncostatin M to endogenous cell surface receptors. Biologicalactivity mediated by such binding of oncostatin M to the cells thus isalso inhibited.

gp130 alone binds oncostatin M, but with relatively low affinity(Gearing et al., Science 255:1434, 1992). Heterodimeric receptorscomprising a leukemia inhibitory factor (LIF) receptor and gp130 bindoncostatin M with higher affinity than does gp130 alone, but also bindLIF with high affinity (Gearing et al., supra). Receptors of the presentinvention, produced by cells co-transfected with OSM-Rβ- andgp130-encoding DNA, for example, bind oncostatin M with high affinitybut do not function as a high affinity LIF receptors. Such receptors ofthe present invention may be employed when inhibition of an oncostatinM-mediated activity, but not a LIF-mediated activity, is desired, forexample. Oncostatin M shares certain properties with LIF, but exhibitsother activities that are not exhibited by LIF. In addition, use of thereceptors of the present invention in vitro assays offers the advantageof allowing one to determine that the assay results are attributable tobinding of oncostain M, but not LIF, by the receptor.

In one embodiment of the invention, a heterodimeric receptor comprisingOSM-Rβ and gp130 is administered in vivo to inhibit a biologicalactivity of oncostatin M. Oncostatin M has exhibited growth modulatingactivity on a variety of different cell types, and has been reported tostimulate hematopoiesis, stimulate epithelial cell proliferation,increase plasmin activity (thereby inducing fibrinolysis), inhibitangiogenesis and supress expression of major histocompatibility complexantigens on endothelial cells. See PCT application WO 9109057 andEuropean patent application no. 422,186. When these or other biologicaleffects of oncostatin M are undesirable, a receptor of the presentinvention may be administered to bind oncostatin M.

The inventive receptor may be administered to a patient in atherapeutically effective amount to treat a disorder mediated byoncostatin M. A disorder is said to be mediated by oncostatin M whenoncostatin M causes (directly or indirectly) or exacerbates thedisorder. Soluble receptor proteins can be used to competitively bind tooncostatin M, thereby inhibiting binding of oncostatin M to endogenouscell surface receptors. Oncostatin M is believed to stimulate productionof the cytokine interleukin-6 (IL-6), as reported by Brown et al., J.Immunol. 147:2175 (1991). Oncostatin M therefore may indirectly mediatedisorders associated with the presence of IL-6. IL-6 has been reportedto be involved in the pathogenesis of AIDS-associated Kaposi's sarcoma(deWit et al., J. Intern. Med. England! 229:539, 1991). Oncostatin M hasbeen reported to play a role in stimulating proliferation of Kaposi'ssarcoma cells (Nair et al., Science 255:1430, 1992, and Miles et al.,Science 255:1432, 1992). Binding of oncostatin M by a receptor of thepresent invention (preferably a soluble form thereof) thus may be usefulin treating Kaposi's sarcoma.

Heterodimeric receptors comprising OSM-Rβ linked to gp130 also find usein assays for biological activity of oncostatin M proteins, whichbiological activity is measured in terms of binding affinity for thereceptor. To illustrate, the receptor may be employed in a binding assayto measure the biological activity of an oncostatin M fragment, variant,or mutein. The receptor is useful for determining whether biologicalactivity of oncostatin M is retained after modification of an oncostatinM protein (e.g., chemical modification, mutation, etc.). The bindingaffinity of the modified oncostatin M protein for the receptor iscompared to that of an unmodified oncostatin M protein to detect anyadverse impact of the modification on biological activity. Biologicalactivity thus can be assessed before the modified protein is used in aresearch study or assay, for example.

The heterodimeric receptors also find use as reagents that may beemployed by those conducting "quality assurance" studies, e.g., tomonitor shelf life and stability of oncostatin M proteins underdifferent conditions. The receptors may be used to confirm biologicalactivity (in terms of binding affinity for the receptor) in oncostatin Mproteins that have been stored at different temperatures, for differentperiods of time, or which have been produced in different types ofrecombinant expression systems, for example.

The present invention further provides fragments of the OSM-Rβnucleotide sequences presented herein. Such fragments desirably compriseat least about 14 nucleotides of the sequence presented in SEQ ID NO:5.DNA and RNA complements of said fragments are provided herein, alongwith both single-stranded and double-stranded forms of the OSM-Rβ DNA.

Among the uses of such nucleic acid fragments is use as a probe. Suchprobes may be employed in cross-species hybridization procedures toisolate OSM-Rβ DNA from additional mammalian species. As one example, aprobe corresponding to the extracellular domain of OSM-Rβ may beemployed. The probes also find use in detecting the presence of OSM-Rβnucleic acids in in vitro assays and in such procedures as Northern andSouthern blots. Cell types expressing OSM-Rβ can be identified. Suchprocedures are well known, and the skilled artisan can choose a probe ofsuitable length, depending on the particular intended application. Theprobes may be labeled (e.g., with ³² P) by conventional techniques.

Other useful fragments of the OSM-Rβ nucleic acids are antisense orsense oligonucleotides comprising a single-stranded nucleic acidsequence (either RNA or DNA) capable of binding to target OSM-Rβ mRNA(sense) or OSM-Rβ DNA (antisense) sequences. Antisense or senseoligonucleotides, according to the present invention, may comprise afragment of the coding region of OSM-Rβ cDNA. Such a fragment generallycomprises at least about 14 nucleotides, preferably from about 14 toabout 30 nucleotides. The ability to create an antisense or a senseoligonucleotide based upon a cDNA sequence for a given protein isdescribed in, for example, Stein and Cohen, Cancer Res. 48:2659, 1988and van der Krol et al., BioTechniques 6:958, 1988.

Binding of antisense or sense oligonucleotides to target nucleic acidsequences results in the formation of duplexes that block translation(RNA) or transcription (DNA) by one of several means, including enhanceddegradation of the duplexes, premature termination of transcription ortranslation, or by other means. The antisense oligonucleotides thus maybe used to block expression of OSM-Rβ proteins.

Antisense or sense oligonucleotides further comprise oligonucleotideshaving modified sugar-phosphodiester backbones (or other sugar linkages,such as those described in WO91/06629) and wherein such sugar linkagesare resistant to endogenous nucleases. Such oligonucleotides withresistant sugar linkages are stable in vivo (i.e., capable of resistingenzymatic degradation) but retain sequence specificity to be able tobind to target nucleotide sequences. Other examples of sense orantisense oligonucleotides include those oligonucleotides which arecovalently linked to organic moieties, such as those described in WO90/10448, and other moieties that increase affinity of theoligonucleotide for a target nucleic acid sequence, such aspoly-(L-lysine). Further still, intercalating agents, such asellipticine, and alkylating agents or metal complexes may be attached tosense or antisense oligonucleotides to modify binding specificities ofthe antisense or sense oligonucleotide for the target nucleotidesequence.

Antisense or sense oligonucleotides may be introduced into a cellcontaining the target nucleic acid sequence by any gene transfer method,including, for example, CaPO₄ -mediated DNA transfection,electroporation, or by using gene transfer vectors such as Epstein-Barrvirus. Antisense or sense oligonucleotides are preferably introducedinto a cell containing the target nucleic acid sequence by insertion ofthe antisense or sense oligonucleotide into a suitable retroviralvector, then contacting the cell with the retroviral vector containingthe inserted sequence, either in vivo or ex vivo. Suitable retroviralvectors include, but are not limited to, those derived from the murineretrovirus M-MuLV, N2 (a retrovirus derived from M-MuLV), or the doublecopy vectors designated DCT5A, DCT5B and DCT5C (see PCT Application WO90/13641).

Sense or antisense oligonucleotides also may be introduced into a cellcontaining the target nucleotide sequence by formation of a conjugatewith a ligand binding molecule, as described in WO 91/04753. Suitableligand binding molecules include, but are not limited to, cell surfacereceptors, growth factors, other cytokines, or other ligands that bindto cell surface receptors.

Alternatively, a sense or an antisense oligonucleotide may be introducedinto a cell containing the target nucleic acid sequence by formation ofan oligonucleotide-lipid complex, as described in WO 90/10448. The senseor antisense oligonucleotide-lipid complex is preferably dissociatedwithin the cell by an endogenous lipase.

The following examples are provided to illustrate certain embodiments ofthe invention, and are not to be construed as limiting the scope of theinvention.

EXAMPLES Example 1 Isolation of DNA Encoding OSM-Rβ

DNA encoding the β subunit of the oncostatin M receptor was isolated asfollows. The procedure began with preparation of oligonucleotidesdegenerate to amino acid sequences that are conserved among proteins ofthe hematopoietin receptor family.

Alignment of the amino acid sequences of three proteins in thehematopoietin receptor family (gp130, LIF receptor, and G-CSF receptor)reveals several highly conserved regions. Such conserved regions areidentified and discussed by Gearing et al. in Polyfunctional Cytokines:IL-6 and LIF, Bock et al., Eds., John Wiley & Sons, Chichester, UK,1992, page 245. After including homologous sequences from the γ chain ofthe IL-2 receptor as well (Takeshita et al. Science 257:379, 1992),oligonucleotides degenerate to certain of the conserved regions (i.e.,sets of oligonucleotides that include all possible DNA sequences thatcan encode the amino acid sequences in the conserved regions) wereprepared by conventional techniques.

Two sets of degenerate oligonucleotides were used as primers in apolymerase chain reaction (PCR). 5' primers were degenerate to the aminoacid sequence PheArgXArgCys (SEQ ID NO:9), which is found at positions275-279 of the gp130 sequence of SEQ ID NO:2, wherein X represents Ile(found at that position in gp130 and LIF-R) or Val (for IL-2Rγ).Additional 5' primers degenerate to the sequence LeuGlnIleArgCys (SEQ IDNO:10), which is found at the corresponding position in G-CSF-R, wereemployed as well. The 3' primers were degenerate to the amino acidsequence TrpSerXTrpSer (SEQ ID NO:11), which is found at positions288-292 of the gp130 sequence of SEQ ID NO:2, wherein X represents Asp(found at that position in gp130 and G-CSF-R), Lys (for LIF-R), or Glu(for IL-2Rγ).

To test the viability of this approach, PCR was conducted using theabove-described primers with LIF-R, gp130, G-CSF-R, or IL-2Rγ DNA as thetemplate. The reactions were conducted by conventional techniques, andthe reaction products were analyzed by gel electrophoresis. For eachreaction, a band about 50 base-pairs in size was seen on the gel,indicating successful amplification of a DNA fragment of the expectedsize.

PCR was then conducted using genomic human DNA as the template. Thereaction products were analyzed by gel electrophoresis, and a 50 bp bandwas visualized. This band was excised from the gel, and the DNA waseluted therefrom. The DNA was subcloned into the cloning vectorpBLUESCRIPT® SK, which is available from Stratagene Cloning Systems, LaJolla, Calif. E. coli cells were transformed with the resultingrecombinant vectors, and individual colonies of the transformants werecultivated in 96-well plates.

Twelve colonies were chosen at random, and the recombinant vectors wereisolated therefrom. The nucleotide sequences of the DNA inserts of thevectors were determined. Seven of these inserts were identified by theirsequence as gp130 DNA, two were LIF-R, one contained a stop codon anddid not appear to be of interest, and two contained a novel sequence(the same sequence, in both orientations). An oligonucleotide probecontaining this novel sequence (the portion of the insert that isbetween the two primer sequences) was prepared and labeled with ³² P bystandard techniques.

The ³² P-labeled probe was used to screen two different cDNA libraries,one derived from human placenta and the other from a cell linedesignated IMTLH-1. The placental library was chosen because placenta isa rich source of growth and differentiation factors. The IMTLH cells,obtained by transformation of human bone marrow stromal cells withpSV-neo, were chosen because they were found to bind oncostatin M butnot LIF (Thoma et al., J. Biol. Chem. 269:6215, 1994). In addition, anRNA band of about 5.5-6.0 kb was detected on Northern blots of RNAderived from IMTLH-1 cells and placenta, probed with theabove-identified ³² P-labeled probe.

Positive clones were isolated from both libraries and determined by DNAsequencing to contain various portions of the novel DNA of interest.Although an initiator codon (indicating the 5' end of a coding region)was identified, none of the clones appeared to contain the stop codonthat would represent the 3' end of the coding region.

An oligonucleotide probe corresponding to sequence found near the 3' endof several of the clones was synthesized and labeled with ³² P bystandard techniques. The probe was used to screen a cDNA library derivedfrom the SV40-transformed human lung fibroblast cell line WI-26 VA4.This library was constructed as described in example 2 of U.S. Pat. No.5,264,416, which is hereby incorporated by reference. Clones comprisingadditional coding sequence at the 3' end (compared to thepreviously-identified clones above) were isolated.

An expression vector was constructed, containing a DNA fragmentcomprising this 3' end of the novel sequence ligated to DNA fragmentsfrom the above-described clones containing the 5' end of the novelsequence. The nucleotide sequence of the human OSM-Rβ DNA in theresulting recombinant vector is presented in SEQ ID NO:5. The proteinencoded by the isolated DNA is presented in SEQ ID NO:6.

The vector was a mammalian expression vector designated pDC409. Thisvector is similar to pDC406, described in McMahan et al., (EMBO J.10:2821, 1991). A BglII site outside the multiple cloning site (mcs) inpDC406 has been deleted so that the BglII site in the mcs of pDC409 isunique. The pDC409 multiple cloning site (mcs) differs from that ofpDC406 in that it contains additional restriction sites and three stopcodons (one in each reading frame). A T7 polymerase promoter downstreamof the mcs facilitates sequencing of DNA inserted into the mcs.

The OSM-Rβ cDNA insert was excised from an expression vector usingrestriction enzymes that cleave within the 5' and 3' non-coding regionsof the cDNA. The excised cDNA was ligated into the EcoRV site of thecloning vector pBluescript® SK⁻ (Stratagene Cloning Systems, LaJolla,Calif.). The Eco RV site, found in the multiple cloning site of thevector, was destroyed by insertion of the cDNA. E. coli cellstransformed with the resulting recombinant vector were deposited withthe American Type Culture Collection, Rockville, Md., U.S.A., on Aug.16, 1994, and assigned accession no. ATCC 69675. The deposit was madeunder the terms of the Budapest Treaty.

The encoded OSM-Rβ amino acid sequence presented in SEQ ID NO:6comprises an N-terminal signal peptide (amino acids -27 to -1) followedby an extracellular domain (amino acids 1 to 714), a transmembraneregion (amino acids 715 to 734) and a cytoplasmic domain (amino acids735 to 952). The OSM-Rβ amino acid sequence is approximately 30%identical to that of the LIF receptor protein described in Gearing etal. (EMBO J. 10:2839, 1991) and in U.S. Pat. No. 5,284,755, herebyincorporated by reference. The DNA sequence of the coding region ofOSM-Rβ is about 48% identical to the portion of LIF-R DNA that alignswith the OSM-Rβ coding region when the above-described GAP computerprogram is employed.

Example 2 Assay to Detect Binding of Oncostatin M

An assay for binding of oncostatin M by cells expressing bothrecombinant gp130 and recombinant OSM-Rβ was conducted as follows. Anassay for oncostatin M binding by cells expressing gp130 alone was alsoconducted for purposes of comparison.

Oncostatin M may be purified from cells in which the protein isnaturally found, or from cells transformed with an expression vectorencoding oncostatin M. One source of oncostatin M is phorbolester-treated U937 cells, as described by Zarling et al., PNAS U.S.A.83:9739 (1986). Purification of recombinant oncostatin M is described byLinsley et al. (J. Biol. Chem. 264:4282-4289, 1989) and Gearing et al.(EMBO J. 10:2839, 1991).

Oncostatin M (OSM) may be radiolabeled using any suitable conventionalprocedure. Radioiodination of oncostatin M has been described by Linsleyet al., supra., for example. In one suitable procedure, OSM isradiolabeled using a commercially available enzymobead radioiodinationreagent (BioRad) according to manufacturer's instructions. The resulting¹²⁵ I-OSM is diluted to a working stock solution in binding medium,which is RPMI 1640 medium containing 2.5% (w/v) bovine serum albumin(BSA), 0.2% (w/v) sodium azide, and 20 mM Hepes, pH 7.4.

CV1-EBNA-1 cells in 150 mm dishes (3.6×10⁶ cells/dish) were transfectedwith a gp130-encoding expression vector, or were co-transfected with thegp130-encoding vector and an OSM-Rβ-encoding vector. All cells wereadditionally co-transfected with a mammalian expression vectordesignated pDC410, described below.

The OSM-Rβ-encoding vector was the recombinant vector described inexample 1, comprising full length OSM-Rβ DNA in mammalian expressionvector pDC409. The gp130-encoding vector comprised the human gp130 DNAsequence of SEQ ID NO:1 in a mammalian expression vector designatedpDC304. A similar recombinant vector, comprising the same gp130-encodingDNA in mammalian expression vector pDC303, was deposited in E. colistrain DH5α host cells with the American Type Culture Collection,Rockville, Md. These transformed cells were deposited under the nameB10G/pDC303 (DH5α) on Nov. 14, 1991 and assigned ATCC Accession No.68827. The deposit was made under the terms of the Budapest Treaty.

pDC304 comprises a NotI site in its multiple cloning site, but isotherwise identical to pDC303. pDC304 also is essentially identical topCAV/NOT, described in PCT application WO 90/05183, except that asegment of the adenovirus-2 tripartite leader (TPL) containing a crypticpromoter functional in bacteria has been deleted. Protein expressionfrom the cryptic promoter is potentially disadvantageous for preparingand isolating a desired recombinant plasmid in bacterial cells.

The pDC410 vector is identical to the pDC409 vector described in example1, except that the EBV origin of replication of pDC409 is replaced byDNA encoding the SV40 large T antigen driven from the SV40 promoter inpDC410. Co-transfecting the cells with this vector provides the SV40T-antigen that drives high level DNA replication of the other plasmidvectors, which contain the SV40 origin of replication. pDC410 thus isimportant for episomal replication of the co-transfected vectors inCV1-EBNA-1 cells.

The transfected cells were cultured for 24 hours, trypsinized andreplated, then cultured another 24 hours to permit expression of theencoded proteins, which were retained on the cell membrane. The adherentcells were dislodged using 5 mM EDTA in PBS, then washed twice withbinding medium (RPMI 1640 medium containing 25 mg/ml bovine serumalbumin, 2 mg/ml sodium azide, and 20 mM HEPES, pH 7.2). The cells thenwere incubated with various concentrations of ¹²⁵ I-labeled oncostatin Min binding medium for 1 hour at 37° C. with gentle agitation.

Free and cell-bound ¹²⁵ I-oncostatin M were separated using thephthalate oil separation method of Dower et al. (J Immunol. 132:751,1984), essentially as described by Park et al. (J. Biol. Chem. 261:4177,1986, and Proc. Natl. Acad. Sci. USA 84:5267, 1987). The free andcell-bound ¹²⁵ I-oncostatin M were quantified on a Packard AutogammaCounter. Affinity calculations (Scatchard, Ann. N.Y. Acad. Sci. 51:660,1949) were generated on RS/1 (BBN Software, Boston, Mass.) run on aMicrovax computer.

The results are presented in FIGS. 1 and 2, in the form of Scatchardanalyses. FIG. 1 presents the results for cells expressing gp130 alone.These transfected cells exhibited a single affinity class of binding,with approximately 29,310 receptor sites per cell, and an affinityconstant (Ka) of 2.64×10⁸. FIG. 2 presents the results for cellsexpressing gp130 and OSM-Rβ. A biphasic pattern can be seen, indicatingtwo binding components. The first component (approximately 2196 receptorsites per cell) exhibited an affinity constant of 7.18×10⁹. The secondcomponent (approximately 36,471 receptor sites per cell) exhibited anaffinity constant of 2.34×10⁸. Thus, a relatively high affinity bindingcomponent is seen in the cells expressing both gp130 and OSM-Rβ. Thesehigh affinity binding sites were absent in the cells expressing gp130alone.

The cells co-transfected with both OSM-Rβ- and gp130-encoding expressionvectors expressed a receptor protein of the present invention. Thereceptor binds oncostatin M with higher affinity than does the gp130protein expressed on cells transfected with the gp130-encoding vectoralone.

Example 3 Preparation of Monoclonal Antibodies Directed Against OSM-Rβ

Purified OSM-Rβ polypeptides of the present invention are employed asimmunogens to generate monoclonal antibodies immunoreactive therewithusing conventional techniques, for example, those disclosed in U.S. Pat.No. 4,411,993. Suitable immunogens include, but are not limited to, fulllength recombinant OSM-Rβ or fragments thereof, such as theextracellular domain. To immunize mice, the immunogen is emulsified incomplete Freund's adjuvant and injected subcutaneously in amountsranging from 10-100 μg into Balb/c mice. Ten to twelve days later, theimmunized animals are boosted with additional immunogen emulsified inincomplete Freund's adjuvant and periodically boosted thereafter on aweekly to biweekly immunization schedule. Serum samples are periodicallytaken by retro-orbital bleeding or tail-tip excision for testing bydot-blot assay (antibody sandwich) or ELISA (enzyme-linked immunosorbentassay). Other assay procedures are also suitable.

Following detection of an appropriate antibody titer, positive animalsare given an intravenous injection of antigen in saline. Three to fourdays later, the animals are sacrificed, splenocytes harvested, and fusedto a murine myeloma cell line, e.g., NS1 or, preferably, P3×63Ag8.653(ATCC CRL 1580). Hybridoma cell lines generated by this procedure areplated in multiple microtiter plates in a HAT selective medium(hypoxantine, aminopterin, and thymidine) to inhibit proliferation ofnon-fused cells, myeloma hybrids, and spleen cell hybrids.

Hybridoma clones thus generated can be screened by ELISA for reactivitywith the receptor protein, for example, by adaptations of the techniquesdisclosed by Engvall et al., Immunochem 8.871 (1971) and in U.S. Pat.No. 4,704,004. A preferred screening technique is the antibody capturetechnique described in Beckmann et al. (J. Immunol. 144:4212, 1990).Positive clones are then injected into the peritoneal cavities ofsyngeneic Balb/c mice to produce ascites containing high concentrations(greater than 1 mg/ml) of anti-OSM-Rβ monoclonal antibody. The resultingmonoclonal antibody can be purified by ammonium sulfate precipitationfollowed by gel exclusion chromatography, and/or affinity chromatographybased on binding of antibody to Protein A of Staphylococcus aureus.

Example 4 Receptors Comprising gp130 Polypeptides Lacking FNIII Domains

DNA sequences encoding soluble gp130 proteins lacking fibronectin typeIII (FNIII) domains were isolated and fused to an Fc-encoding sequence.Deleting the FNIII domains affords the advantage of reducing the size ofthe gp130/Fc fusion protein. gp130 contains three FNIII domains,comprising amino acids 300 (Tyr) to 399 (Phe), 400 (Gln) to 496 (Pro),and 497 (Pro) to 597 (Glu), respectively, of SEQ ID NO:2. From one toall three of the FNIII domains may be removed from gp130 to reduce thesize of the protein.

The FNIII domains of gp130 were removed by digesting a recombinantgp130/Fc-encoding expression vector with BstX1, then blunting theoverhang using T4 DNA polymerase according to conventional procedures.The recognition site for BstX1 spans nucleotides 1231-1242 of SEQ IDNO:1 (gp130), cleaving within the codons for amino acids 10-11 of thefirst FNIII domain of gp130. The cleaved vector was then digested withEcoR5, which cleaves within the polylinker of the vector upstream of theFc sequence and generates blunt ends. The (BstX1)/EcoR5 fragmentcomprising a sequence encoding the 5' end of gp130 (lacking the FNIIIdomains), the vector sequences, the Fc sequence, and a portion of thepolylinker, was ligated to recircularize the vector.

E. coli cells were transformed with the ligation mixture, plasmids wereisolated therefrom, and the desired recombinant plasmid was identifiedby restriction analysis. The fusion protein encoded by the constructcomprises (from N- to C-terminus) amino acids -22 to 308 of SEQ ID NO:2(gp130), a four amino acid spacer peptide -Asn-Arg-Tyr-Val- encoded bythe polylinker segment, and amino acids 1-232 of SEQ ID NO:3 (Fc). Thegp130 polypeptide moiety contains the first 9 amino acids of the firstFNIII domain, but lacks the remainder of the first FNIII domain and allof the second and third FNIII domains.

A heterodimeric receptor of the present invention may comprise OSM-Rβand the foregoing truncated gp130 polypeptide lacking FNIII domains.COS-7 cells or other suitable host cells are co-transfected withOSM-Rβ-encoding and truncated gp130-encoding expression vectors. Theco-transfected cells are cultured to express the heterodimeric receptor.

Example 5 Assay for Binding of Oncostatin M and LIF by Receptors

An assay for binding of oncostatin M or leukemia inhibitory factor (LIF)by various receptor proteins was conducted as follows. The receptorproteins included soluble OSM-Rβ/Fc, gp130/Fc, LIF-R/Fc, andcombinations thereof. Results of the assay are presented in FIG. 3.

An expression vector encoding a soluble OSM-Rβ/Fc fusion protein, whichcomprised a truncated extracellular domain of OSM-Rβ fused to theN-terminus of an Fc region polypeptide derived from an antibody, wasconstructed as follows. The recombinant expression vector prepared inexample 1, comprising OSM-Rβ DNA in vector pDC409, was digested with therestriction enzyme SphI, treated with T4 DNA polymerase to remove the 3'overhangs (generating blunt ends), then digested with Sal I, whichcleaves upstream of the OSM-Rβ coding region. The desired fragment,which includes the 5' end of the OSM-Rβ DNA, terminating at nucleotide1744 of SEQ ID NO:5, was isolated by conventional techniques.

A recombinant vector designated hIgG1Fc comprises the Fcpolypeptide-encoding cDNA of SEQ ID NO:3, as described above. VectorhIgG1Fc was digested with the restriction enzymes Sna B1 and NotI, whichcleave in the polylinker region of the vector, upstream and downstream,respectively, of the Fc polypeptide-encoding cDNA.

The thus-isolated Fc polypeptide-encoding DNA fragment and theOSM-Rβ-encoding DNA fragment isolated above were ligated into aSalI/NotI-digested expression vector pDC304 such that the Fc polypeptideDNA was fused to the 3' end of the OSM-Rβ DNA. The mammalian expressionvector pDC304 is described in example 2. The resulting expression vectorencoded a fusion protein comprising amino acids -27 through 432 of theOSM-Rβ sequence of SEQ ID NO:6, followed by a valine residue encoded bya vector polylinker segment, followed by amino acids 1 through 232 ofthe Fc polypeptide sequence of SEQ ID NO:4.

An expression vector encoding a soluble human gp130/Fc fusion proteinwas constructed as follows. Recombinant vector B10G/pDC303 (ATCC 68827)comprising human gp130 cDNA was digested with EcoR1, and the resulting5' overhang was rendered blunt using T4 DNA polymerase. The recognitionsite for EcoR1 comprises nucleotides 2056-2061 of SEQ ID NO:1. TheEcoR1-digested vector was then cleaved with XhoI, which cleaves in thevector upstream of the gp130 cDNA insert.

Vector hIgG1Fc, comprising Fc polypeptide-encoding cDNA as describedabove, was digested with StuI (a blunt cutter) and NotI, which cleaveupstream and downstream, respectively, of the inserted Fc cDNA. TheXhoI/(EcoR1) gp130 fragment isolated above was ligated to theFc-containing fragment and to XhoI/NotI-digested mammalian expressionvector pDC304.

E. coli cells were transformed with the ligation mixture, plasmids wereisolated therefrom by conventional procedures, and the desiredrecombinant vector was identified by restriction analysis. The gp130/Fcfusion protein encoded by the recombinant vector comprises (from N- toC-terminus) amino acids -22 to 582 of SEQ ID NO:2 (gp130), followed by 7amino acids constituting a peptide linker encoded by the polylinkersegment of plasmid hIgG1Fc, followed by amino acids 1-232 of SEQ ID NO:4(Fc).

An expression vector encoding a soluble human LIF-R/Fc fusion proteinwas constructed as described in example 5 of U.S. Pat. No. 5,284,755,hereby incorporated by reference. Briefly, a recombinant vectordesignated pHLIF-R-65 contains human LIF-R cDNA (a partial cloneencoding a complete signal peptide, extracellular domain, andtransmembrane region, and a partial cytoplasmic domain) in vectorpDC303. The mammalian expression vector pDC303 is described in PCTapplication WO 93/19777. E. coli cells transformed with pHLIF-R-65 weredeposited with the American Type Culture Collection, Rockville, Md., onDec. 11, 1990, and assigned accession no. 68491. DNA encoding the LIF-Rsignal peptide and extracellular domain (truncated at the C-terminus)was isolated and fused to DNA encoding an antibody Fc region polypeptidein pBluescript®SK⁻. The gene fusion was excised from the cloning vectorand inserted into the above-described mammalian expression vectorpDC304. The resulting recombinant expression vector encoded a LIF-R/Fcfusion protein comprising amino acids -44 through 702 of the LIF-Rsequence presented in U.S. Pat. No. 5,284,755, followed by a linkercomprising six amino acids encoded by a vector polylinker segment,followed by amino acids 1 through 232 of the Fc amino acid sequence ofSEQ ID NO:4.

CV-1-EBNA cells were transfected with one of the three recombinantexpression vectors prepared above, or co-transfected with two of thevectors, as follows:

    ______________________________________    Experiment   Cells transfected with vector(s) encoding:    ______________________________________    A            empty expression vector (control)    B            gp130/Fc    C            LIF-R/Fc    D            OSM-Rβ/Fc    E            OSM-Rβ/Fc and LIF-R/Fc    F            OSM-Rβ/Fc and gp130/Fc    G            gp130/Fc and LIF-R/Fc    ______________________________________

The transfected cells were cultured to allow expression and secretion ofthe fusion proteins into the culture medium. Cross-linked agarose beadsbearing Protein A (Protein A Sepharose CL-4B, Pharmacia Biotech, Inc.,Piscataway, N.J.) were added to the culture supernatants, whereupon thefusion proteins bound to the beads via the interaction of the Fc moietywith the Protein A. Radioiodinated oncostatin M or radioiodinated LIFwas also added to the culture supernatants. Preparation of ¹²⁵I-oncostatin M is described in example 2 above. Among the knownprocedures for purifying and radioiodinating LIF are those described inexample 1 of U.S. Pat. No. 5,284,755. The ¹²⁵ I-LIF employed in thisassay was recombinant human LIF labeled with ¹²⁵ I using the enzymobeadreagent (BioRad).

The culture supernatants were incubated with the Protein A beads and ¹²⁵I-LIF or ¹²⁵ I-oncostatin M for 18 hours at 4° C. Free and cell-bound¹²⁵ I-LIF or ¹²⁵ I-oncostatin M were separated by low speedcentrifugation through a single step density gradient of 3% glucose inPBS. The bead-bound radioiodinated proteins were quantified on a PackardAutogamma counter.

The results are presented in FIG. 3. The bar graph in FIG. 3 representsthe binding of oncostatin M or LIF to the proteins expressed by cellstransfected as described above for experiments A to G. The expressedproteins are bound to the Protein A beads.

Experiment A (control) revealed no significant binding of LIF oroncostatin M to proteins expressed by cells transfected with the emptyexpression vector pDC304. The soluble gp130/Fc protein bound oncostatinM, but no significant binding of LIF was demonstrated (experiment B).The soluble LIF-R/Fc protein bound LIF, but not oncostatin M (experimentC). No detectable binding of LIF or oncostatin M by the solubleOSM-Rβ/Fc protein was demonstrated (experiment D).

Proteins expressed by cells co-transfected with soluble LIF-R/Fc andOSM-Rβ encoding vectors did not bind detectable quantities of oncostatinM, but bound LIF (experiment E). Proteins expressed by cellsco-transfected with soluble OSM-Rβ/Fc and soluble gp130/Fc encodingvectors bound oncostatin M, but did not bind detectable quantities ofLIF (experiment F). The binding of oncostatin M in experiment F could beinhibited by including unlabeled (cold) oncostatin M in the assay. Theproteins expressed by cells co-transfected with expression vectorsencoding soluble gp130/Fc and LIF-R/Fc (experiment G) bound bothoncostatin M and LIF. The LIF binding in experiment G was inhibited byadding cold LIF to the assay.

The proteins expressed when cells are co-transfected with vectorsencoding soluble OSM-Rβ/Fc and soluble gp130/Fc, in accordance with thepresent invention, thus bind oncostatin M but not LIF. This isadvantageous when binding of oncostatin M (e.g., to inhibit or study abiological activity thereof) is desired, but binding of LIF is notdesired. The proteins expressed by cells co-transfected with solublegp130/Fc and soluble LIF-R/Fc encoding vectors bind both oncostatin Mand LIF, and thus do not offer this advantageous property. In addition,cells expressing both soluble OSM-Rβ/Fc and soluble gp130/Fc boundoncostatin M at a higher level than did cells expressing solublegp130/Fc alone.

BRIEF DESCRIPTION OF THE SEQUENCE LISTING

SEQ ID NO:1 and SEQ ID NO:2 present the DNA sequence and encoded aminoacid sequence for cloned cDNA encoding an N-terminal fragment of gp130.

SEQ ID NO:3 and SEQ ID NO:4 present the DNA sequence and encoded aminoacid sequence for cloned cDNA encoding a polypeptide that corresponds tothe Fc region of an IgG1 antibody.

SEQ ID NO:5 and SEQ ID NO:6 present the DNA and encoded amino acidsequence for cloned cDNA encoding the oncostatin M receptor β subunit ofthe present invention.

SEQ ID NO:7 presents the amino acid sequence of a peptide that may beemployed to facilitate purification of polypeptides fused thereto.

SEQ ID NO:8 presents a spacer peptide encoded by a polylinker in anexpression vector, as described in example 4.

SEQ ID NOS:9, 10, and 11 are peptides that correspond to conservedsequences, as described in example 1.

    __________________________________________________________________________    #             SEQUENCE LISTING    - (1) GENERAL INFORMATION:    -    (iii) NUMBER OF SEQUENCES: 11    - (2) INFORMATION FOR SEQ ID NO:1:    -      (i) SEQUENCE CHARACTERISTICS:    #pairs    (A) LENGTH: 2369 base              (B) TYPE: nucleic acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: cDNA to mRNA    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -      (v) FRAGMENT TYPE: N-terminal    -     (vi) ORIGINAL SOURCE:    #placenta (F) TISSUE TYPE: human    -    (vii) IMMEDIATE SOURCE:              (B) CLONE: B10G/pDC303    -     (ix) FEATURE:              (A) NAME/KEY: CDS              (B) LOCATION: 244..2369    -     (ix) FEATURE:              (A) NAME/KEY: mat.sub.-- - #peptide              (B) LOCATION: 310..2369    -     (ix) FEATURE:              (A) NAME/KEY: sig.sub.-- - #peptide              (B) LOCATION: 244..309    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:    - GGCCCGCGGA GTCGCGCTGG GCCGCCCCGG CGCAGCTGAA CCGGGGGCCG CG - #CCTGCCAG      60    - GCCGACGGGT CTGGCCCAGC CTGGCGCCAA GGGGTTCGTG CGCTGTGGAG AC - #GCGGAGGG     120    - TCGAGGCGGC GCGGCCTGAG TGAAACCCAA TGGAAAAAGC ATGACATTTA GA - #AGTAGAAG     180    - ACTTAGCTTC AAATCCCTAC TCCTTCACTT ACTAATTTTG TGATTTGGAA AT - #ATCCGCGC     240    - AAG ATG TTG ACG TTG CAG ACT TGG CTA GTG CA - #A GCC TTG TTT ATT TTC     288    #Val Gln Ala Leu Phe Ile PheTrp Leu    10    - CTC ACC ACT GAA TCT ACA GGT GAA CTT CTA GA - #T CCA TGT GGT TAT ATC     336    Leu Thr Thr Glu Ser Thr Gly Glu Leu Leu As - #p Pro Cys Gly Tyr Ile    #       5  1    - AGT CCT GAA TCT CCA GTT GTA CAA CTT CAT TC - #T AAT TTC ACT GCA GTT     384    Ser Pro Glu Ser Pro Val Val Gln Leu His Se - #r Asn Phe Thr Ala Val    # 25    - TGT GTG CTA AAG GAA AAA TGT ATG GAT TAT TT - #T CAT GTA AAT GCT AAT     432    Cys Val Leu Lys Glu Lys Cys Met Asp Tyr Ph - #e His Val Asn Ala Asn    #                 40    - TAC ATT GTC TGG AAA ACA AAC CAT TTT ACT AT - #T CCT AAG GAG CAA TAT     480    Tyr Ile Val Trp Lys Thr Asn His Phe Thr Il - #e Pro Lys Glu Gln Tyr    #             55    - ACT ATC ATA AAC AGA ACA GCA TCC AGT GTC AC - #C TTT ACA GAT ATA GCT     528    Thr Ile Ile Asn Arg Thr Ala Ser Ser Val Th - #r Phe Thr Asp Ile Ala    #         70    - TCA TTA AAT ATT CAG CTC ACT TGC AAC ATT CT - #T ACA TTC GGA CAG CTT     576    Ser Leu Asn Ile Gln Leu Thr Cys Asn Ile Le - #u Thr Phe Gly Gln Leu    #     85    - GAA CAG AAT GTT TAT GGA ATC ACA ATA ATT TC - #A GGC TTG CCT CCA GAA     624    Glu Gln Asn Val Tyr Gly Ile Thr Ile Ile Se - #r Gly Leu Pro Pro Glu    #105    - AAA CCT AAA AAT TTG AGT TGC ATT GTG AAC GA - #G GGG AAG AAA ATG AGG     672    Lys Pro Lys Asn Leu Ser Cys Ile Val Asn Gl - #u Gly Lys Lys Met Arg    #               120    - TGT GAG TGG GAT GGT GGA AGG GAA ACA CAC TT - #G GAG ACA AAC TTC ACT     720    Cys Glu Trp Asp Gly Gly Arg Glu Thr His Le - #u Glu Thr Asn Phe Thr    #           135    - TTA AAA TCT GAA TGG GCA ACA CAC AAG TTT GC - #T GAT TGC AAA GCA AAA     768    Leu Lys Ser Glu Trp Ala Thr His Lys Phe Al - #a Asp Cys Lys Ala Lys    #       150    - CGT GAC ACC CCC ACC TCA TGC ACT GTT GAT TA - #T TCT ACT GTG TAT TTT     816    Arg Asp Thr Pro Thr Ser Cys Thr Val Asp Ty - #r Ser Thr Val Tyr Phe    #   165    - GTC AAC ATT GAA GTC TGG GTA GAA GCA GAG AA - #T GCC CTT GGG AAG GTT     864    Val Asn Ile Glu Val Trp Val Glu Ala Glu As - #n Ala Leu Gly Lys Val    170                 1 - #75                 1 - #80                 1 -    #85    - ACA TCA GAT CAT ATC AAT TTT GAT CCT GTA TA - #T AAA GTG AAG CCC AAT     912    Thr Ser Asp His Ile Asn Phe Asp Pro Val Ty - #r Lys Val Lys Pro Asn    #               200    - CCG CCA CAT AAT TTA TCA GTG ATC AAC TCA GA - #G GAA CTG TCT AGT ATC     960    Pro Pro His Asn Leu Ser Val Ile Asn Ser Gl - #u Glu Leu Ser Ser Ile    #           215    - TTA AAA TTG ACA TGG ACC AAC CCA AGT ATT AA - #G AGT GTT ATA ATA CTA    1008    Leu Lys Leu Thr Trp Thr Asn Pro Ser Ile Ly - #s Ser Val Ile Ile Leu    #       230    - AAA TAT AAC ATT CAA TAT AGG ACC AAA GAT GC - #C TCA ACT TGG AGC CAG    1056    Lys Tyr Asn Ile Gln Tyr Arg Thr Lys Asp Al - #a Ser Thr Trp Ser Gln    #   245    - ATT CCT CCT GAA GAC ACA GCA TCC ACC CGA TC - #T TCA TTC ACT GTC CAA    1104    Ile Pro Pro Glu Asp Thr Ala Ser Thr Arg Se - #r Ser Phe Thr Val Gln    250                 2 - #55                 2 - #60                 2 -    #65    - GAC CTT AAA CCT TTT ACA GAA TAT GTG TTT AG - #G ATT CGC TGT ATG AAG    1152    Asp Leu Lys Pro Phe Thr Glu Tyr Val Phe Ar - #g Ile Arg Cys Met Lys    #               280    - GAA GAT GGT AAG GGA TAC TGG AGT GAC TGG AG - #T GAA GAA GCA AGT GGG    1200    Glu Asp Gly Lys Gly Tyr Trp Ser Asp Trp Se - #r Glu Glu Ala Ser Gly    #           295    - ATC ACC TAT GAA GAT AGA CCA TCT AAA GCA CC - #A AGT TTC TGG TAT AAA    1248    Ile Thr Tyr Glu Asp Arg Pro Ser Lys Ala Pr - #o Ser Phe Trp Tyr Lys    #       310    - ATA GAT CCA TCC CAT ACT CAA GGC TAC AGA AC - #T GTA CAA CTC GTG TGG    1296    Ile Asp Pro Ser His Thr Gln Gly Tyr Arg Th - #r Val Gln Leu Val Trp    #   325    - AAG ACA TTG CCT CCT TTT GAA GCC AAT GGA AA - #A ATC TTG GAT TAT GAA    1344    Lys Thr Leu Pro Pro Phe Glu Ala Asn Gly Ly - #s Ile Leu Asp Tyr Glu    330                 3 - #35                 3 - #40                 3 -    #45    - GTG ACT CTC ACA AGA TGG AAA TCA CAT TTA CA - #A AAT TAC ACA GTT AAT    1392    Val Thr Leu Thr Arg Trp Lys Ser His Leu Gl - #n Asn Tyr Thr Val Asn    #               360    - GCC ACA AAA CTG ACA GTA AAT CTC ACA AAT GA - #T CGC TAT CTA GCA ACC    1440    Ala Thr Lys Leu Thr Val Asn Leu Thr Asn As - #p Arg Tyr Leu Ala Thr    #           375    - CTA ACA GTA AGA AAT CTT GTT GGC AAA TCA GA - #T GCA GCT GTT TTA ACT    1488    Leu Thr Val Arg Asn Leu Val Gly Lys Ser As - #p Ala Ala Val Leu Thr    #       390    - ATC CCT GCC TGT GAC TTT CAA GCT ACT CAC CC - #T GTA ATG GAT CTT AAA    1536    Ile Pro Ala Cys Asp Phe Gln Ala Thr His Pr - #o Val Met Asp Leu Lys    #   405    - GCA TTC CCC AAA GAT AAC ATG CTT TGG GTG GA - #A TGG ACT ACT CCA AGG    1584    Ala Phe Pro Lys Asp Asn Met Leu Trp Val Gl - #u Trp Thr Thr Pro Arg    410                 4 - #15                 4 - #20                 4 -    #25    - GAA TCT GTA AAG AAA TAT ATA CTT GAG TGG TG - #T GTG TTA TCA GAT AAA    1632    Glu Ser Val Lys Lys Tyr Ile Leu Glu Trp Cy - #s Val Leu Ser Asp Lys    #               440    - GCA CCC TGT ATC ACA GAC TGG CAA CAA GAA GA - #T GGT ACC GTG CAT CGC    1680    Ala Pro Cys Ile Thr Asp Trp Gln Gln Glu As - #p Gly Thr Val His Arg    #           455    - ACC TAT TTA AGA GGG AAC TTA GCA GAG AGC AA - #A TGC TAT TTG ATA ACA    1728    Thr Tyr Leu Arg Gly Asn Leu Ala Glu Ser Ly - #s Cys Tyr Leu Ile Thr    #       470    - GTT ACT CCA GTA TAT GCT GAT GGA CCA GGA AG - #C CCT GAA TCC ATA AAG    1776    Val Thr Pro Val Tyr Ala Asp Gly Pro Gly Se - #r Pro Glu Ser Ile Lys    #   485    - GCA TAC CTT AAA CAA GCT CCA CCT TCC AAA GG - #A CCT ACT GTT CGG ACA    1824    Ala Tyr Leu Lys Gln Ala Pro Pro Ser Lys Gl - #y Pro Thr Val Arg Thr    490                 4 - #95                 5 - #00                 5 -    #05    - AAA AAA GTA GGG AAA AAC GAA GCT GTC TTA GA - #G TGG GAC CAA CTT CCT    1872    Lys Lys Val Gly Lys Asn Glu Ala Val Leu Gl - #u Trp Asp Gln Leu Pro    #               520    - GTT GAT GTT CAG AAT GGA TTT ATC AGA AAT TA - #T ACT ATA TTT TAT AGA    1920    Val Asp Val Gln Asn Gly Phe Ile Arg Asn Ty - #r Thr Ile Phe Tyr Arg    #           535    - ACC ATC ATT GGA AAT GAA ACT GCT GTG AAT GT - #G GAT TCT TCC CAC ACA    1968    Thr Ile Ile Gly Asn Glu Thr Ala Val Asn Va - #l Asp Ser Ser His Thr    #       550    - GAA TAT ACA TTG TCC TCT TTG ACT AGT GAC AC - #A TTG TAC ATG GTA CGA    2016    Glu Tyr Thr Leu Ser Ser Leu Thr Ser Asp Th - #r Leu Tyr Met Val Arg    #   565    - ATG GCA GCA TAC ACA GAT GAA GGT GGG AAG GA - #T GGT CCA GAA TTC ACT    2064    Met Ala Ala Tyr Thr Asp Glu Gly Gly Lys As - #p Gly Pro Glu Phe Thr    570                 5 - #75                 5 - #80                 5 -    #85    - TTT ACT ACC CCA AAG TTT GCT CAA GGA GAA AT - #T GAA GCC ATA GTC GTG    2112    Phe Thr Thr Pro Lys Phe Ala Gln Gly Glu Il - #e Glu Ala Ile Val Val    #               600    - CCT GTT TGC TTA GCA TTC CTA TTG ACA ACT CT - #T CTG GGA GTG CTG TTC    2160    Pro Val Cys Leu Ala Phe Leu Leu Thr Thr Le - #u Leu Gly Val Leu Phe    #           615    - TGC TTT AAT AAG CGA GAC CTA ATT AAA AAA CA - #C ATC TGG CCT AAT GTT    2208    Cys Phe Asn Lys Arg Asp Leu Ile Lys Lys Hi - #s Ile Trp Pro Asn Val    #       630    - CCA GAT CCT TCA AAG AGT CAT ATT GCC CAG TG - #G TCA CCT CAC ACT CCT    2256    Pro Asp Pro Ser Lys Ser His Ile Ala Gln Tr - #p Ser Pro His Thr Pro    #   645    - CCA AGG CAC AAT TTT AAT TCA AAA GAT CAA AT - #G TAT TCA GAT GGC AAT    2304    Pro Arg His Asn Phe Asn Ser Lys Asp Gln Me - #t Tyr Ser Asp Gly Asn    650                 6 - #55                 6 - #60                 6 -    #65    - TTC ACT GAT GTA AGT GTT GTG GAA ATA GAA GC - #A AAT GAC AAA AAG CCT    2352    Phe Thr Asp Val Ser Val Val Glu Ile Glu Al - #a Asn Asp Lys Lys Pro    #               680    # 2369             TG AA    Phe Pro Glu Asp Leu                685    - (2) INFORMATION FOR SEQ ID NO:2:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 708 amino              (B) TYPE: amino acid              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: protein    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:    - Met Leu Thr Leu Gln Thr Trp Leu Val Gln Al - #a Leu Phe Ile Phe Leu    10    - Thr Thr Glu Ser Thr Gly Glu Leu Leu Asp Pr - #o Cys Gly Tyr Ile Ser    #   10    - Pro Glu Ser Pro Val Val Gln Leu His Ser As - #n Phe Thr Ala Val Cys    #                 25    - Val Leu Lys Glu Lys Cys Met Asp Tyr Phe Hi - #s Val Asn Ala Asn Tyr    #             40    - Ile Val Trp Lys Thr Asn His Phe Thr Ile Pr - #o Lys Glu Gln Tyr Thr    #         55    - Ile Ile Asn Arg Thr Ala Ser Ser Val Thr Ph - #e Thr Asp Ile Ala Ser    #     70    - Leu Asn Ile Gln Leu Thr Cys Asn Ile Leu Th - #r Phe Gly Gln Leu Glu    # 90    - Gln Asn Val Tyr Gly Ile Thr Ile Ile Ser Gl - #y Leu Pro Pro Glu Lys    #                105    - Pro Lys Asn Leu Ser Cys Ile Val Asn Glu Gl - #y Lys Lys Met Arg Cys    #           120    - Glu Trp Asp Gly Gly Arg Glu Thr His Leu Gl - #u Thr Asn Phe Thr Leu    #       135    - Lys Ser Glu Trp Ala Thr His Lys Phe Ala As - #p Cys Lys Ala Lys Arg    #   150    - Asp Thr Pro Thr Ser Cys Thr Val Asp Tyr Se - #r Thr Val Tyr Phe Val    155                 1 - #60                 1 - #65                 1 -    #70    - Asn Ile Glu Val Trp Val Glu Ala Glu Asn Al - #a Leu Gly Lys Val Thr    #               185    - Ser Asp His Ile Asn Phe Asp Pro Val Tyr Ly - #s Val Lys Pro Asn Pro    #           200    - Pro His Asn Leu Ser Val Ile Asn Ser Glu Gl - #u Leu Ser Ser Ile Leu    #       215    - Lys Leu Thr Trp Thr Asn Pro Ser Ile Lys Se - #r Val Ile Ile Leu Lys    #   230    - Tyr Asn Ile Gln Tyr Arg Thr Lys Asp Ala Se - #r Thr Trp Ser Gln Ile    235                 2 - #40                 2 - #45                 2 -    #50    - Pro Pro Glu Asp Thr Ala Ser Thr Arg Ser Se - #r Phe Thr Val Gln Asp    #               265    - Leu Lys Pro Phe Thr Glu Tyr Val Phe Arg Il - #e Arg Cys Met Lys Glu    #           280    - Asp Gly Lys Gly Tyr Trp Ser Asp Trp Ser Gl - #u Glu Ala Ser Gly Ile    #       295    - Thr Tyr Glu Asp Arg Pro Ser Lys Ala Pro Se - #r Phe Trp Tyr Lys Ile    #   310    - Asp Pro Ser His Thr Gln Gly Tyr Arg Thr Va - #l Gln Leu Val Trp Lys    315                 3 - #20                 3 - #25                 3 -    #30    - Thr Leu Pro Pro Phe Glu Ala Asn Gly Lys Il - #e Leu Asp Tyr Glu Val    #               345    - Thr Leu Thr Arg Trp Lys Ser His Leu Gln As - #n Tyr Thr Val Asn Ala    #           360    - Thr Lys Leu Thr Val Asn Leu Thr Asn Asp Ar - #g Tyr Leu Ala Thr Leu    #       375    - Thr Val Arg Asn Leu Val Gly Lys Ser Asp Al - #a Ala Val Leu Thr Ile    #   390    - Pro Ala Cys Asp Phe Gln Ala Thr His Pro Va - #l Met Asp Leu Lys Ala    395                 4 - #00                 4 - #05                 4 -    #10    - Phe Pro Lys Asp Asn Met Leu Trp Val Glu Tr - #p Thr Thr Pro Arg Glu    #               425    - Ser Val Lys Lys Tyr Ile Leu Glu Trp Cys Va - #l Leu Ser Asp Lys Ala    #           440    - Pro Cys Ile Thr Asp Trp Gln Gln Glu Asp Gl - #y Thr Val His Arg Thr    #       455    - Tyr Leu Arg Gly Asn Leu Ala Glu Ser Lys Cy - #s Tyr Leu Ile Thr Val    #   470    - Thr Pro Val Tyr Ala Asp Gly Pro Gly Ser Pr - #o Glu Ser Ile Lys Ala    475                 4 - #80                 4 - #85                 4 -    #90    - Tyr Leu Lys Gln Ala Pro Pro Ser Lys Gly Pr - #o Thr Val Arg Thr Lys    #               505    - Lys Val Gly Lys Asn Glu Ala Val Leu Glu Tr - #p Asp Gln Leu Pro Val    #           520    - Asp Val Gln Asn Gly Phe Ile Arg Asn Tyr Th - #r Ile Phe Tyr Arg Thr    #       535    - Ile Ile Gly Asn Glu Thr Ala Val Asn Val As - #p Ser Ser His Thr Glu    #   550    - Tyr Thr Leu Ser Ser Leu Thr Ser Asp Thr Le - #u Tyr Met Val Arg Met    555                 5 - #60                 5 - #65                 5 -    #70    - Ala Ala Tyr Thr Asp Glu Gly Gly Lys Asp Gl - #y Pro Glu Phe Thr Phe    #               585    - Thr Thr Pro Lys Phe Ala Gln Gly Glu Ile Gl - #u Ala Ile Val Val Pro    #           600    - Val Cys Leu Ala Phe Leu Leu Thr Thr Leu Le - #u Gly Val Leu Phe Cys    #       615    - Phe Asn Lys Arg Asp Leu Ile Lys Lys His Il - #e Trp Pro Asn Val Pro    #   630    - Asp Pro Ser Lys Ser His Ile Ala Gln Trp Se - #r Pro His Thr Pro Pro    635                 6 - #40                 6 - #45                 6 -    #50    - Arg His Asn Phe Asn Ser Lys Asp Gln Met Ty - #r Ser Asp Gly Asn Phe    #               665    - Thr Asp Val Ser Val Val Glu Ile Glu Ala As - #n Asp Lys Lys Pro Phe    #           680    - Pro Glu Asp Leu            685    - (2) INFORMATION FOR SEQ ID NO:3:    -      (i) SEQUENCE CHARACTERISTICS:    #pairs    (A) LENGTH: 705 base              (B) TYPE: nucleic acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: cDNA to mRNA    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -    (vii) IMMEDIATE SOURCE:              (B) CLONE: hIgG1Fc    -     (ix) FEATURE:              (A) NAME/KEY: CDS              (B) LOCATION: 1..699    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:    - GAG CCC AGA TCT TGT GAC AAA ACT CAC ACA TG - #C CCA CCG TGC CCA GCA      48    Glu Pro Arg Ser Cys Asp Lys Thr His Thr Cy - #s Pro Pro Cys Pro Ala    #                 15    - CCT GAA CTC CTG GGG GGA CCG TCA GTC TTC CT - #C TTC CCC CCA AAA CCC      96    Pro Glu Leu Leu Gly Gly Pro Ser Val Phe Le - #u Phe Pro Pro Lys Pro    #             30    - AAG GAC ACC CTC ATG ATC TCC CGG ACC CCT GA - #G GTC ACA TGC GTG GTG     144    Lys Asp Thr Leu Met Ile Ser Arg Thr Pro Gl - #u Val Thr Cys Val Val    #         45    - GTG GAC GTG AGC CAC GAA GAC CCT GAG GTC AA - #G TTC AAC TGG TAC GTG     192    Val Asp Val Ser His Glu Asp Pro Glu Val Ly - #s Phe Asn Trp Tyr Val    #     60    - GAC GGC GTG GAG GTG CAT AAT GCC AAG ACA AA - #G CCG CGG GAG GAG CAG     240    Asp Gly Val Glu Val His Asn Ala Lys Thr Ly - #s Pro Arg Glu Glu Gln    # 80    - TAC AAC AGC ACG TAC CGG GTG GTC AGC GTC CT - #C ACC GTC CTG CAC CAG     288    Tyr Asn Ser Thr Tyr Arg Val Val Ser Val Le - #u Thr Val Leu His Gln    #                 95    - GAC TGG CTG AAT GGC AAG GAC TAC AAG TGC AA - #G GTC TCC AAC AAA GCC     336    Asp Trp Leu Asn Gly Lys Asp Tyr Lys Cys Ly - #s Val Ser Asn Lys Ala    #           110    - CTC CCA GCC CCC ATG CAG AAA ACC ATC TCC AA - #A GCC AAA GGG CAG CCC     384    Leu Pro Ala Pro Met Gln Lys Thr Ile Ser Ly - #s Ala Lys Gly Gln Pro    #       125    - CGA GAA CCA CAG GTG TAC ACC CTG CCC CCA TC - #C CGG GAT GAG CTG ACC     432    Arg Glu Pro Gln Val Tyr Thr Leu Pro Pro Se - #r Arg Asp Glu Leu Thr    #   140    - AAG AAC CAG GTC AGC CTG ACC TGC CTG GTC AA - #A GGC TTC TAT CCC AGG     480    Lys Asn Gln Val Ser Leu Thr Cys Leu Val Ly - #s Gly Phe Tyr Pro Arg    145                 1 - #50                 1 - #55                 1 -    #60    - CAC ATC GCC GTG GAG TGG GAG AGC AAT GGG CA - #G CCG GAG AAC AAC TAC     528    His Ile Ala Val Glu Trp Glu Ser Asn Gly Gl - #n Pro Glu Asn Asn Tyr    #               175    - AAG ACC ACG CCT CCC GTG CTG GAC TCC GAC GG - #C TCC TTC TTC CTC TAC     576    Lys Thr Thr Pro Pro Val Leu Asp Ser Asp Gl - #y Ser Phe Phe Leu Tyr    #           190    - AGC AAG CTC ACC GTG GAC AAG AGC AGG TGG CA - #G CAG GGG AAC GTC TTC     624    Ser Lys Leu Thr Val Asp Lys Ser Arg Trp Gl - #n Gln Gly Asn Val Phe    #       205    - TCA TGC TCC GTG ATG CAT GAG GCT CTG CAC AA - #C CAC TAC ACG CAG AAG     672    Ser Cys Ser Val Met His Glu Ala Leu His As - #n His Tyr Thr Gln Lys    #   220    #        705       CT CCG GGT AAA TGAACTAGT    Ser Leu Ser Leu Ser Pro Gly Lys    225                 2 - #30    - (2) INFORMATION FOR SEQ ID NO:4:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 232 amino              (B) TYPE: amino acid              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: protein    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:    - Glu Pro Arg Ser Cys Asp Lys Thr His Thr Cy - #s Pro Pro Cys Pro Ala    #                 15    - Pro Glu Leu Leu Gly Gly Pro Ser Val Phe Le - #u Phe Pro Pro Lys Pro    #             30    - Lys Asp Thr Leu Met Ile Ser Arg Thr Pro Gl - #u Val Thr Cys Val Val    #         45    - Val Asp Val Ser His Glu Asp Pro Glu Val Ly - #s Phe Asn Trp Tyr Val    #     60    - Asp Gly Val Glu Val His Asn Ala Lys Thr Ly - #s Pro Arg Glu Glu Gln    # 80    - Tyr Asn Ser Thr Tyr Arg Val Val Ser Val Le - #u Thr Val Leu His Gln    #                 95    - Asp Trp Leu Asn Gly Lys Asp Tyr Lys Cys Ly - #s Val Ser Asn Lys Ala    #           110    - Leu Pro Ala Pro Met Gln Lys Thr Ile Ser Ly - #s Ala Lys Gly Gln Pro    #       125    - Arg Glu Pro Gln Val Tyr Thr Leu Pro Pro Se - #r Arg Asp Glu Leu Thr    #   140    - Lys Asn Gln Val Ser Leu Thr Cys Leu Val Ly - #s Gly Phe Tyr Pro Arg    145                 1 - #50                 1 - #55                 1 -    #60    - His Ile Ala Val Glu Trp Glu Ser Asn Gly Gl - #n Pro Glu Asn Asn Tyr    #               175    - Lys Thr Thr Pro Pro Val Leu Asp Ser Asp Gl - #y Ser Phe Phe Leu Tyr    #           190    - Ser Lys Leu Thr Val Asp Lys Ser Arg Trp Gl - #n Gln Gly Asn Val Phe    #       205    - Ser Cys Ser Val Met His Glu Ala Leu His As - #n His Tyr Thr Gln Lys    #   220    - Ser Leu Ser Leu Ser Pro Gly Lys    225                 2 - #30    - (2) INFORMATION FOR SEQ ID NO:5:    -      (i) SEQUENCE CHARACTERISTICS:    #pairs    (A) LENGTH: 4171 base              (B) TYPE: nucleic acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: cDNA to mRNA    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -    (vii) IMMEDIATE SOURCE:              (B) CLONE: huOSM-Ra    -     (ix) FEATURE:              (A) NAME/KEY: sig.sub.-- - #peptide              (B) LOCATION: 368..448    -     (ix) FEATURE:              (A) NAME/KEY: CDS              (B) LOCATION: 368..3307    -     (ix) FEATURE:              (A) NAME/KEY: mat.sub.-- - #peptide              (B) LOCATION: 449..3304    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:    - GGGCCGCCTC TGCACGTCCG CCCCGGAGCC CGCACCCGCG CCCCACGCGC CG - #CCGAGGAC      60    - TCGGCCCGGC TCGTGGAGCC CTTCGCCCGC GGCGTGAGTA CCCCCGACCC GC - #CCGTCCCC     120    - GCTCTGCTCG CGCCCTGCCG CTGCGCCGCC CTCGGTGGCT TTTCCGACGG GC - #GAGCCCCG     180    - TGCTGTGCGG GAAAGAATCC GACAACTTCG CAGCCCATCC CGGCTGGACG CG - #ACCGGGAG     240    - TGCAGCAGCC CGTTCCCCTC CTCGGTGCCG CCTCTGCCCA GCGTTTGCTT GG - #CTGGGCTA     300    - CCACCTGCGC TCGGACGGCG CTCGGAGGGT CCTCGCCCCC GGCCTGCCTA CC - #TGAAAACC     360    #ACA TTC TTC TTA ACA      409 GTC TTT CAG ACA    #Phe Gln Thr Thr Phe Phe Leu Thr    15    - TTG CTG TCC TTG AGG ACT TAC CAG AGT GAA GT - #C TTG GCT GAA CGT TTA     457    Leu Leu Ser Leu Arg Thr Tyr Gln Ser Glu Va - #l Leu Ala Glu Arg Leu    #             1    - CCA TTG ACT CCT GTA TCA CTT AAA GTT TCC AC - #C AAT TCT ACG CGT CAG     505    Pro Leu Thr Pro Val Ser Leu Lys Val Ser Th - #r Asn Ser Thr Arg Gln    #      15    - AGT TTG CAC TTA CAA TGG ACT GTC CAC AAC CT - #T CCT TAT CAT CAG GAA     553    Ser Leu His Leu Gln Trp Thr Val His Asn Le - #u Pro Tyr His Gln Glu    # 35    - TTG AAA ATG GTA TTT CAG ATC CAG ATC AGT AG - #G ATT GAA ACA TCC AAT     601    Leu Lys Met Val Phe Gln Ile Gln Ile Ser Ar - #g Ile Glu Thr Ser Asn    #                 50    - GTC ATC TGG GTG GGG AAT TAC AGC ACC ACT GT - #G AAG TGG AAC CAG GTT     649    Val Ile Trp Val Gly Asn Tyr Ser Thr Thr Va - #l Lys Trp Asn Gln Val    #             65    - CTG CAT TGG AGC TGG GAA TCT GAG CTC CCT TT - #G GAA TGT GCC ACA CAC     697    Leu His Trp Ser Trp Glu Ser Glu Leu Pro Le - #u Glu Cys Ala Thr His    #         80    - TTT GTA AGA ATA AAG AGT TTG GTG GAC GAT GC - #C AAG TTC CCT GAG CCA     745    Phe Val Arg Ile Lys Ser Leu Val Asp Asp Al - #a Lys Phe Pro Glu Pro    #     95    - AAT TTC TGG AGC AAC TGG AGT TCC TGG GAG GA - #A GTC AGT GTA CAA GAT     793    Asn Phe Trp Ser Asn Trp Ser Ser Trp Glu Gl - #u Val Ser Val Gln Asp    100                 1 - #05                 1 - #10                 1 -    #15    - TCT ACT GGA CAG GAT ATA TTG TTC GTT TTC CC - #T AAA GAT AAG CTG GTG     841    Ser Thr Gly Gln Asp Ile Leu Phe Val Phe Pr - #o Lys Asp Lys Leu Val    #               130    - GAA GAA GGC ACC AAT GTT ACC ATT TGT TAC GT - #T TCT AGG AAC ATT CAA     889    Glu Glu Gly Thr Asn Val Thr Ile Cys Tyr Va - #l Ser Arg Asn Ile Gln    #           145    - AAT AAT GTA TCC TGT TAT TTG GAA GGG AAA CA - #G ATT CAT GGA GAA CAA     937    Asn Asn Val Ser Cys Tyr Leu Glu Gly Lys Gl - #n Ile His Gly Glu Gln    #       160    - CTT GAT CCA CAT GTA ACT GCA TTC AAC TTG AA - #T AGT GTG CCT TTC ATT     985    Leu Asp Pro His Val Thr Ala Phe Asn Leu As - #n Ser Val Pro Phe Ile    #   175    - AGG AAT AAA GGG ACA AAT ATC TAT TGT GAG GC - #A AGT CAA GGA AAT GTC    1033    Arg Asn Lys Gly Thr Asn Ile Tyr Cys Glu Al - #a Ser Gln Gly Asn Val    180                 1 - #85                 1 - #90                 1 -    #95    - AGT GAA GGC ATG AAA GGC ATC GTT CTT TTT GT - #C TCA AAA GTA CTT GAG    1081    Ser Glu Gly Met Lys Gly Ile Val Leu Phe Va - #l Ser Lys Val Leu Glu    #               210    - GAG CCC AAG GAC TTT TCT TGT GAA ACC GAG GA - #C TTC AAG ACT TTG CAC    1129    Glu Pro Lys Asp Phe Ser Cys Glu Thr Glu As - #p Phe Lys Thr Leu His    #           225    - TGT ACT TGG GAT CCT GGG ACG GAC ACT GCC TT - #G GGG TGG TCT AAA CAA    1177    Cys Thr Trp Asp Pro Gly Thr Asp Thr Ala Le - #u Gly Trp Ser Lys Gln    #       240    - CCT TCC CAA AGC TAC ACT TTA TTT GAA TCA TT - #T TCT GGG GAA AAG AAA    1225    Pro Ser Gln Ser Tyr Thr Leu Phe Glu Ser Ph - #e Ser Gly Glu Lys Lys    #   255    - CTT TGT ACA CAC AAA AAC TGG TGT AAT TGG CA - #A ATA ACT CAA GAC TCA    1273    Leu Cys Thr His Lys Asn Trp Cys Asn Trp Gl - #n Ile Thr Gln Asp Ser    260                 2 - #65                 2 - #70                 2 -    #75    - CAA GAA ACC TAT AAC TTC ACA CTC ATA GCT GA - #A AAT TAC TTA AGG AAG    1321    Gln Glu Thr Tyr Asn Phe Thr Leu Ile Ala Gl - #u Asn Tyr Leu Arg Lys    #               290    - AGA AGT GTC AAT ATC CTT TTT AAC CTG ACT CA - #T CGA GTT TAT TTA ATG    1369    Arg Ser Val Asn Ile Leu Phe Asn Leu Thr Hi - #s Arg Val Tyr Leu Met    #           305    - AAT CCT TTT AGT GTC AAC TTT GAA AAT GTA AA - #T GCC ACA AAT GCC ATC    1417    Asn Pro Phe Ser Val Asn Phe Glu Asn Val As - #n Ala Thr Asn Ala Ile    #       320    - ATG ACC TGG AAG GTG CAC TCC ATA AGG AAT AA - #T TTC ACA TAT TTG TGT    1465    Met Thr Trp Lys Val His Ser Ile Arg Asn As - #n Phe Thr Tyr Leu Cys    #   335    - CAG ATT GAA CTC CAT GGT GAA GGA AAA ATG AT - #G CAA TAC AAT GTT TCC    1513    Gln Ile Glu Leu His Gly Glu Gly Lys Met Me - #t Gln Tyr Asn Val Ser    340                 3 - #45                 3 - #50                 3 -    #55    - ATC AAG GTG AAC GGT GAG TAC TTC TTA AGT GA - #A CTG GAA CCT GCC ACA    1561    Ile Lys Val Asn Gly Glu Tyr Phe Leu Ser Gl - #u Leu Glu Pro Ala Thr    #               370    - GAG TAC ATG GCG CGA GTA CGG TGT GCT GAT GC - #C AGC CAC TTC TGG AAA    1609    Glu Tyr Met Ala Arg Val Arg Cys Ala Asp Al - #a Ser His Phe Trp Lys    #           385    - TGG AGT GAA TGG AGT GGT CAG AAC TTC ACC AC - #A CTT GAA GCT GCT CCC    1657    Trp Ser Glu Trp Ser Gly Gln Asn Phe Thr Th - #r Leu Glu Ala Ala Pro    #       400    - TCA GAG GCC CCT GAT GTC TGG AGA ATT GTG AG - #C TTG GAG CCA GGA AAT    1705    Ser Glu Ala Pro Asp Val Trp Arg Ile Val Se - #r Leu Glu Pro Gly Asn    #   415    - CAT ACT GTG ACC TTA TTC TGG AAG CCA TTA TC - #A AAA CTG CAT GCC AAT    1753    His Thr Val Thr Leu Phe Trp Lys Pro Leu Se - #r Lys Leu His Ala Asn    420                 4 - #25                 4 - #30                 4 -    #35    - GGA AAG ATC CTG TTC TAT AAT GTA GTT GTA GA - #A AAC CTA GAC AAA CCA    1801    Gly Lys Ile Leu Phe Tyr Asn Val Val Val Gl - #u Asn Leu Asp Lys Pro    #               450    - TCC AGT TCA GAG CTC CAT TCC ATT CCA GCA CC - #A GCC AAC AGC ACA AAA    1849    Ser Ser Ser Glu Leu His Ser Ile Pro Ala Pr - #o Ala Asn Ser Thr Lys    #           465    - CTA ATC CTT GAC AGG TGT TCC TAC CAA ATC TG - #C GTC ATA GCC AAC AAC    1897    Leu Ile Leu Asp Arg Cys Ser Tyr Gln Ile Cy - #s Val Ile Ala Asn Asn    #       480    - AGT GTG GGT GCT TCT CCT GCT TCT GTA ATA GT - #C ATC TCT GCA GAC CCC    1945    Ser Val Gly Ala Ser Pro Ala Ser Val Ile Va - #l Ile Ser Ala Asp Pro    #   495    - GAA AAC AAA GAG GTT GAG GAA GAA AGA ATT GC - #A GGC ACA GAG GGT GGA    1993    Glu Asn Lys Glu Val Glu Glu Glu Arg Ile Al - #a Gly Thr Glu Gly Gly    500                 5 - #05                 5 - #10                 5 -    #15    - TTC TCT CTG TCT TGG AAA CCC CAA CCT GGA GA - #T GTT ATA GGC TAT GTT    2041    Phe Ser Leu Ser Trp Lys Pro Gln Pro Gly As - #p Val Ile Gly Tyr Val    #               530    - GTG GAC TGG TGT GAC CAT ACC CAG GAT GTG CT - #C GGT GAT TTC CAG TGG    2089    Val Asp Trp Cys Asp His Thr Gln Asp Val Le - #u Gly Asp Phe Gln Trp    #           545    - AAG AAT GTA GGT CCC AAT ACC ACA AGC ACA GT - #C ATT AGC ACA GAT GCT    2137    Lys Asn Val Gly Pro Asn Thr Thr Ser Thr Va - #l Ile Ser Thr Asp Ala    #       560    - TTT AGG CCA GGA GTT CGA TAT GAC TTC AGA AT - #T TAT GGG TTA TCT ACA    2185    Phe Arg Pro Gly Val Arg Tyr Asp Phe Arg Il - #e Tyr Gly Leu Ser Thr    #   575    - AAA AGG ATT GCT TGT TTA TTA GAG AAA AAA AC - #A GGA TAC TCT CAG GAA    2233    Lys Arg Ile Ala Cys Leu Leu Glu Lys Lys Th - #r Gly Tyr Ser Gln Glu    580                 5 - #85                 5 - #90                 5 -    #95    - CTT GCT CCT TCA GAC AAC CCT CAC GTG CTG GT - #G GAT ACA TTG ACA TCC    2281    Leu Ala Pro Ser Asp Asn Pro His Val Leu Va - #l Asp Thr Leu Thr Ser    #               610    - CAC TCC TTC ACT CTG AGT TGG AAA GAT TAC TC - #T ACT GAA TCT CAA CCT    2329    His Ser Phe Thr Leu Ser Trp Lys Asp Tyr Se - #r Thr Glu Ser Gln Pro    #           625    - GGT TTT ATA CAA GGG TAC CAT GTC TAT CTG AA - #A TCC AAG GCG AGG CAG    2377    Gly Phe Ile Gln Gly Tyr His Val Tyr Leu Ly - #s Ser Lys Ala Arg Gln    #       640    - TGC CAC CCA CGA TTT GAA AAG GCA GTT CTT TC - #A GAT GGT TCA GAA TGT    2425    Cys His Pro Arg Phe Glu Lys Ala Val Leu Se - #r Asp Gly Ser Glu Cys    #   655    - TGC AAA TAC AAA ATT GAC AAC CCG GAA GAA AA - #G GCA TTG ATT GTG GAC    2473    Cys Lys Tyr Lys Ile Asp Asn Pro Glu Glu Ly - #s Ala Leu Ile Val Asp    660                 6 - #65                 6 - #70                 6 -    #75    - AAC CTA AAG CCA GAA TCC TTC TAT GAG TTT TT - #C ATC ACT CCA TTC ACT    2521    Asn Leu Lys Pro Glu Ser Phe Tyr Glu Phe Ph - #e Ile Thr Pro Phe Thr    #               690    - AGT GCT GGT GAA GGC CCC AGT GCT ACG TTC AC - #G AAG GTC ACG ACT CCG    2569    Ser Ala Gly Glu Gly Pro Ser Ala Thr Phe Th - #r Lys Val Thr Thr Pro    #           705    - GAT GAA CAC TCC TCG ATG CTG ATT CAT ATC CT - #A CTG CCC ATG GTT TTC    2617    Asp Glu His Ser Ser Met Leu Ile His Ile Le - #u Leu Pro Met Val Phe    #       720    - TGC GTC TTG CTC ATC ATG GTC ATG TGC TAC TT - #G AAA AGT CAG TGG ATC    2665    Cys Val Leu Leu Ile Met Val Met Cys Tyr Le - #u Lys Ser Gln Trp Ile    #   735    - AAG GAG ACC TGT TAT CCT GAC ATC CCT GAC CC - #T TAC AAG AGC AGC ATC    2713    Lys Glu Thr Cys Tyr Pro Asp Ile Pro Asp Pr - #o Tyr Lys Ser Ser Ile    740                 7 - #45                 7 - #50                 7 -    #55    - CTG TCA TTA ATA AAA TTC AAG GAG AAC CCT CA - #C CTA ATA ATA ATG AAT    2761    Leu Ser Leu Ile Lys Phe Lys Glu Asn Pro Hi - #s Leu Ile Ile Met Asn    #               770    - GTC AGT GAC TGT ATC CCA GAT GCT ATT GAA GT - #T GTA AGC AAG CCA GAA    2809    Val Ser Asp Cys Ile Pro Asp Ala Ile Glu Va - #l Val Ser Lys Pro Glu    #           785    - GGG ACA AAG ATA CAG TTC CTA GGC ACT AGG AA - #G TCA CTC ACA GAA ACC    2857    Gly Thr Lys Ile Gln Phe Leu Gly Thr Arg Ly - #s Ser Leu Thr Glu Thr    #       800    - GAG TTG ACT AAG CCT AAC TAC CTT TAT CTC CT - #T CCA ACA GAA AAG AAT    2905    Glu Leu Thr Lys Pro Asn Tyr Leu Tyr Leu Le - #u Pro Thr Glu Lys Asn    #   815    - CAC TCT GGC CCT GGC CCC TGC ATC TGT TTT GA - #G AAC TTG ACC TAT AAC    2953    His Ser Gly Pro Gly Pro Cys Ile Cys Phe Gl - #u Asn Leu Thr Tyr Asn    820                 8 - #25                 8 - #30                 8 -    #35    - CAG GCA GCT TCT GAC TCT GGC TCT TGT GGC CA - #T GTT CCA GTA TCC CCA    3001    Gln Ala Ala Ser Asp Ser Gly Ser Cys Gly Hi - #s Val Pro Val Ser Pro    #               850    - AAA GCC CCA AGT ATG CTG GGA CTA ATG ACC TC - #A CCT GAA AAT GTA CTA    3049    Lys Ala Pro Ser Met Leu Gly Leu Met Thr Se - #r Pro Glu Asn Val Leu    #           865    - AAG GCA CTA GAA AAA AAC TAC ATG AAC TCC CT - #G GGA GAA ATC CCA GCT    3097    Lys Ala Leu Glu Lys Asn Tyr Met Asn Ser Le - #u Gly Glu Ile Pro Ala    #       880    - GGA GAA ACA AGT TTG AAT TAT GTG TCC CAG TT - #G GCT TCA CCC ATG TTT    3145    Gly Glu Thr Ser Leu Asn Tyr Val Ser Gln Le - #u Ala Ser Pro Met Phe    #   895    - GGA GAC AAG GAC AGT CTC CCA ACA AAC CCA GT - #A GAG GCA CCA CAC TGT    3193    Gly Asp Lys Asp Ser Leu Pro Thr Asn Pro Va - #l Glu Ala Pro His Cys    900                 9 - #05                 9 - #10                 9 -    #15    - TCA GAG TAT AAA ATG CAA ATG GCA GTC TCC CT - #G CGT CTT GCC TTG CCT    3241    Ser Glu Tyr Lys Met Gln Met Ala Val Ser Le - #u Arg Leu Ala Leu Pro    #               930    - CCC CCG ACC GAG AAT AGC AGC CTC TCC TCA AT - #T ACC CTT TTA GAT CCA    3289    Pro Pro Thr Glu Asn Ser Ser Leu Ser Ser Il - #e Thr Leu Leu Asp Pro    #           945    - GGT GAA CAC TAC TGC TAACCAGCAT GCCGATTTCA TACCTTATG - #C TACACAGACA    3344    Gly Glu His Tyr Cys            950    - TTAAGAAGAG CAGAGCTGGC ACCCTGTCAT CACCAGTGGC CTTGGTCCTT AA - #TCCCAGTA    3404    - CAATTTGCAG GTCTGGTTTA TATAAGACCA CTACAGTCTG GCTAGGTTAA AG - #GCCAGAGG    3464    - CTATGGAACT TAACACTCCC CATTGGAGCA AGCTTGCCCT AGAGACGGCA GG - #ATCATGGG    3524    - AGCATGCTTA CCTTCTGCTG TTTGTTCCAG GCTCACCTTT AGAACAGGAG AC - #TTGAGCTT    3584    - GACCTAAGGA TATGCATTAA CCACTCTACA GACTCCCACT CAGTACTGTA CA - #GGGTGGCT    3644    - GTGGTCCTAG AAGTTCAGTT TTTACTGAGG AAATATTTCC ATTAACAGCA AT - #TATTATAT    3704    - TGAAGGCTTT AATAAAGGCC ACAGGAGACA TTACTATAGC ATAGATTGTC AA - #ATGTAAAT    3764    - TTACTGAGCG TGTTTTATAA AAAACTCACA GGTGTTTGAG GCCAAAACAG AT - #TTTAGACT    3824    - TACCTTGAAC GGATAAGAAT CTATAGTTCA CTGACACAGT AAAATTAACT CT - #GTGGGTGG    3884    - GGGCGGGGGG CATAGCTCTA ATCTAATATA TAAAATGTGT GATGAATCAA CA - #AGATTTCC    3944    - ACAATTCTTC TGTCAAGCTT ACTACAGTGA AAGAATGGGA TTGGCAAGTA AC - #TTCTGACT    4004    - TACTGTCAGT TGTACTTCTG CTCCATAGAC ATCAGTATTC TGCCATCATT TT - #TGATGACT    4064    - ACCTCAGAAC ATAAAAAGGA ACGTATATCA CATAATTCCA GTCACAGTTT TT - #GGTTCCTC    4124    #              4171ATAT ATAAATGACC TGTTTTCACG CGGCCGC    - (2) INFORMATION FOR SEQ ID NO:6:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 979 amino              (B) TYPE: amino acid              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: protein    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:    - Met Ala Leu Phe Ala Val Phe Gln Thr Thr Ph - #e Phe Leu Thr Leu Leu    15    - Ser Leu Arg Thr Tyr Gln Ser Glu Val Leu Al - #a Glu Arg Leu Pro Leu    #  5  1    - Thr Pro Val Ser Leu Lys Val Ser Thr Asn Se - #r Thr Arg Gln Ser Leu    #                 20    - His Leu Gln Trp Thr Val His Asn Leu Pro Ty - #r His Gln Glu Leu Lys    #             35    - Met Val Phe Gln Ile Gln Ile Ser Arg Ile Gl - #u Thr Ser Asn Val Ile    #         50    - Trp Val Gly Asn Tyr Ser Thr Thr Val Lys Tr - #p Asn Gln Val Leu His    #     65    - Trp Ser Trp Glu Ser Glu Leu Pro Leu Glu Cy - #s Ala Thr His Phe Val    # 85    - Arg Ile Lys Ser Leu Val Asp Asp Ala Lys Ph - #e Pro Glu Pro Asn Phe    #                100    - Trp Ser Asn Trp Ser Ser Trp Glu Glu Val Se - #r Val Gln Asp Ser Thr    #           115    - Gly Gln Asp Ile Leu Phe Val Phe Pro Lys As - #p Lys Leu Val Glu Glu    #       130    - Gly Thr Asn Val Thr Ile Cys Tyr Val Ser Ar - #g Asn Ile Gln Asn Asn    #   145    - Val Ser Cys Tyr Leu Glu Gly Lys Gln Ile Hi - #s Gly Glu Gln Leu Asp    150                 1 - #55                 1 - #60                 1 -    #65    - Pro His Val Thr Ala Phe Asn Leu Asn Ser Va - #l Pro Phe Ile Arg Asn    #               180    - Lys Gly Thr Asn Ile Tyr Cys Glu Ala Ser Gl - #n Gly Asn Val Ser Glu    #           195    - Gly Met Lys Gly Ile Val Leu Phe Val Ser Ly - #s Val Leu Glu Glu Pro    #       210    - Lys Asp Phe Ser Cys Glu Thr Glu Asp Phe Ly - #s Thr Leu His Cys Thr    #   225    - Trp Asp Pro Gly Thr Asp Thr Ala Leu Gly Tr - #p Ser Lys Gln Pro Ser    230                 2 - #35                 2 - #40                 2 -    #45    - Gln Ser Tyr Thr Leu Phe Glu Ser Phe Ser Gl - #y Glu Lys Lys Leu Cys    #               260    - Thr His Lys Asn Trp Cys Asn Trp Gln Ile Th - #r Gln Asp Ser Gln Glu    #           275    - Thr Tyr Asn Phe Thr Leu Ile Ala Glu Asn Ty - #r Leu Arg Lys Arg Ser    #       290    - Val Asn Ile Leu Phe Asn Leu Thr His Arg Va - #l Tyr Leu Met Asn Pro    #   305    - Phe Ser Val Asn Phe Glu Asn Val Asn Ala Th - #r Asn Ala Ile Met Thr    310                 3 - #15                 3 - #20                 3 -    #25    - Trp Lys Val His Ser Ile Arg Asn Asn Phe Th - #r Tyr Leu Cys Gln Ile    #               340    - Glu Leu His Gly Glu Gly Lys Met Met Gln Ty - #r Asn Val Ser Ile Lys    #           355    - Val Asn Gly Glu Tyr Phe Leu Ser Glu Leu Gl - #u Pro Ala Thr Glu Tyr    #       370    - Met Ala Arg Val Arg Cys Ala Asp Ala Ser Hi - #s Phe Trp Lys Trp Ser    #   385    - Glu Trp Ser Gly Gln Asn Phe Thr Thr Leu Gl - #u Ala Ala Pro Ser Glu    390                 3 - #95                 4 - #00                 4 -    #05    - Ala Pro Asp Val Trp Arg Ile Val Ser Leu Gl - #u Pro Gly Asn His Thr    #               420    - Val Thr Leu Phe Trp Lys Pro Leu Ser Lys Le - #u His Ala Asn Gly Lys    #           435    - Ile Leu Phe Tyr Asn Val Val Val Glu Asn Le - #u Asp Lys Pro Ser Ser    #       450    - Ser Glu Leu His Ser Ile Pro Ala Pro Ala As - #n Ser Thr Lys Leu Ile    #   465    - Leu Asp Arg Cys Ser Tyr Gln Ile Cys Val Il - #e Ala Asn Asn Ser Val    470                 4 - #75                 4 - #80                 4 -    #85    - Gly Ala Ser Pro Ala Ser Val Ile Val Ile Se - #r Ala Asp Pro Glu Asn    #               500    - Lys Glu Val Glu Glu Glu Arg Ile Ala Gly Th - #r Glu Gly Gly Phe Ser    #           515    - Leu Ser Trp Lys Pro Gln Pro Gly Asp Val Il - #e Gly Tyr Val Val Asp    #       530    - Trp Cys Asp His Thr Gln Asp Val Leu Gly As - #p Phe Gln Trp Lys Asn    #   545    - Val Gly Pro Asn Thr Thr Ser Thr Val Ile Se - #r Thr Asp Ala Phe Arg    550                 5 - #55                 5 - #60                 5 -    #65    - Pro Gly Val Arg Tyr Asp Phe Arg Ile Tyr Gl - #y Leu Ser Thr Lys Arg    #               580    - Ile Ala Cys Leu Leu Glu Lys Lys Thr Gly Ty - #r Ser Gln Glu Leu Ala    #           595    - Pro Ser Asp Asn Pro His Val Leu Val Asp Th - #r Leu Thr Ser His Ser    #       610    - Phe Thr Leu Ser Trp Lys Asp Tyr Ser Thr Gl - #u Ser Gln Pro Gly Phe    #   625    - Ile Gln Gly Tyr His Val Tyr Leu Lys Ser Ly - #s Ala Arg Gln Cys His    630                 6 - #35                 6 - #40                 6 -    #45    - Pro Arg Phe Glu Lys Ala Val Leu Ser Asp Gl - #y Ser Glu Cys Cys Lys    #               660    - Tyr Lys Ile Asp Asn Pro Glu Glu Lys Ala Le - #u Ile Val Asp Asn Leu    #           675    - Lys Pro Glu Ser Phe Tyr Glu Phe Phe Ile Th - #r Pro Phe Thr Ser Ala    #       690    - Gly Glu Gly Pro Ser Ala Thr Phe Thr Lys Va - #l Thr Thr Pro Asp Glu    #   705    - His Ser Ser Met Leu Ile His Ile Leu Leu Pr - #o Met Val Phe Cys Val    710                 7 - #15                 7 - #20                 7 -    #25    - Leu Leu Ile Met Val Met Cys Tyr Leu Lys Se - #r Gln Trp Ile Lys Glu    #               740    - Thr Cys Tyr Pro Asp Ile Pro Asp Pro Tyr Ly - #s Ser Ser Ile Leu Ser    #           755    - Leu Ile Lys Phe Lys Glu Asn Pro His Leu Il - #e Ile Met Asn Val Ser    #       770    - Asp Cys Ile Pro Asp Ala Ile Glu Val Val Se - #r Lys Pro Glu Gly Thr    #   785    - Lys Ile Gln Phe Leu Gly Thr Arg Lys Ser Le - #u Thr Glu Thr Glu Leu    790                 7 - #95                 8 - #00                 8 -    #05    - Thr Lys Pro Asn Tyr Leu Tyr Leu Leu Pro Th - #r Glu Lys Asn His Ser    #               820    - Gly Pro Gly Pro Cys Ile Cys Phe Glu Asn Le - #u Thr Tyr Asn Gln Ala    #           835    - Ala Ser Asp Ser Gly Ser Cys Gly His Val Pr - #o Val Ser Pro Lys Ala    #       850    - Pro Ser Met Leu Gly Leu Met Thr Ser Pro Gl - #u Asn Val Leu Lys Ala    #   865    - Leu Glu Lys Asn Tyr Met Asn Ser Leu Gly Gl - #u Ile Pro Ala Gly Glu    870                 8 - #75                 8 - #80                 8 -    #85    - Thr Ser Leu Asn Tyr Val Ser Gln Leu Ala Se - #r Pro Met Phe Gly Asp    #               900    - Lys Asp Ser Leu Pro Thr Asn Pro Val Glu Al - #a Pro His Cys Ser Glu    #           915    - Tyr Lys Met Gln Met Ala Val Ser Leu Arg Le - #u Ala Leu Pro Pro Pro    #       930    - Thr Glu Asn Ser Ser Leu Ser Ser Ile Thr Le - #u Leu Asp Pro Gly Glu    #   945    - His Tyr Cys    950    - (2) INFORMATION FOR SEQ ID NO:7:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 8 amino              (B) TYPE: amino acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: peptide    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -    (vii) IMMEDIATE SOURCE:              (B) CLONE: FLAG peptide    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:    - Asp Tyr Lys Asp Asp Asp Asp Lys    1               5    - (2) INFORMATION FOR SEQ ID NO:8:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 4 amino              (B) TYPE: amino acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: peptide    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -    (vii) IMMEDIATE SOURCE:              (B) CLONE: spacer pepti - #de    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:8:    - Asn Arg Tyr Val    - (2) INFORMATION FOR SEQ ID NO:9:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 5 amino              (B) TYPE: amino acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: peptide    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:9:    - Phe Arg Xaa Arg Cys    1               5    - (2) INFORMATION FOR SEQ ID NO:10:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 5 amino              (B) TYPE: amino acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: peptide    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:10:    - Leu Gln Ile Arg Cys    1               5    - (2) INFORMATION FOR SEQ ID NO:11:    -      (i) SEQUENCE CHARACTERISTICS:    #acids    (A) LENGTH: 5 amino              (B) TYPE: amino acid              (C) STRANDEDNESS: single              (D) TOPOLOGY: linear    -     (ii) MOLECULE TYPE: peptide    -    (iii) HYPOTHETICAL: NO    -     (iv) ANTI-SENSE: NO    -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:11:    - Trp Ser Xaa Trp Ser    1               5    __________________________________________________________________________

What is claimed is:
 1. An isolated antibody that is immunoreactive withan oncostatin M receptor β (OSM-Rβ) polypeptide encoded by a DNAselected from the group consisting of:a) DNA comprising the codingregion of the nucleotide sequence presented in SEQ ID NO:5; b) DNAcapable of hybridizing to the DNA of (a), under highly stringentconditions that include hybridization at 68° C. followed by washing in0.1× SSC/0.1% SDS at 63°-68° C., and encoding a polypeptide having theability to enhance the binding of oncostatin M when OSM-Rβ is joined togp130 compared to the level of oncostatin M binding to gp130 alone; andc) DNA that encodes the amino acid sequence presented in SEQ ID NO:6. 2.An antibody according to claim 1, wherein said antibody is a monoclonalantibody.